mirror of https://github.com/k3s-io/k3s
Merge pull request #35583 from justinsb/replace_ratelimit
Automatic merge from submit-queue Create simple version of ratelimit package Allows for better testing.pull/6/head
commit
cc7070d5d8
|
@ -1484,10 +1484,6 @@
|
|||
"Comment": "v3.0.7-72-ga0ff256",
|
||||
"Rev": "a0ff2567cfb70903282db057e799fd826784d41d"
|
||||
},
|
||||
{
|
||||
"ImportPath": "github.com/juju/ratelimit",
|
||||
"Rev": "77ed1c8a01217656d2080ad51981f6e99adaa177"
|
||||
},
|
||||
{
|
||||
"ImportPath": "github.com/kardianos/osext",
|
||||
"Rev": "8fef92e41e22a70e700a96b29f066cda30ea24ef"
|
||||
|
|
|
@ -50866,205 +50866,6 @@ http://creativecommons.org/publicdomain/zero/1.0
|
|||
================================================================================
|
||||
|
||||
|
||||
================================================================================
|
||||
= vendor/github.com/juju/ratelimit licensed under: =
|
||||
|
||||
All files in this repository are licensed as follows. If you contribute
|
||||
to this repository, it is assumed that you license your contribution
|
||||
under the same license unless you state otherwise.
|
||||
|
||||
All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file.
|
||||
|
||||
This software is licensed under the LGPLv3, included below.
|
||||
|
||||
As a special exception to the GNU Lesser General Public License version 3
|
||||
("LGPL3"), the copyright holders of this Library give you permission to
|
||||
convey to a third party a Combined Work that links statically or dynamically
|
||||
to this Library without providing any Minimal Corresponding Source or
|
||||
Minimal Application Code as set out in 4d or providing the installation
|
||||
information set out in section 4e, provided that you comply with the other
|
||||
provisions of LGPL3 and provided that you meet, for the Application the
|
||||
terms and conditions of the license(s) which apply to the Application.
|
||||
|
||||
Except as stated in this special exception, the provisions of LGPL3 will
|
||||
continue to comply in full to this Library. If you modify this Library, you
|
||||
may apply this exception to your version of this Library, but you are not
|
||||
obliged to do so. If you do not wish to do so, delete this exception
|
||||
statement from your version. This exception does not (and cannot) modify any
|
||||
license terms which apply to the Application, with which you must still
|
||||
comply.
|
||||
|
||||
|
||||
GNU LESSER GENERAL PUBLIC LICENSE
|
||||
Version 3, 29 June 2007
|
||||
|
||||
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
|
||||
This version of the GNU Lesser General Public License incorporates
|
||||
the terms and conditions of version 3 of the GNU General Public
|
||||
License, supplemented by the additional permissions listed below.
|
||||
|
||||
0. Additional Definitions.
|
||||
|
||||
As used herein, "this License" refers to version 3 of the GNU Lesser
|
||||
General Public License, and the "GNU GPL" refers to version 3 of the GNU
|
||||
General Public License.
|
||||
|
||||
"The Library" refers to a covered work governed by this License,
|
||||
other than an Application or a Combined Work as defined below.
|
||||
|
||||
An "Application" is any work that makes use of an interface provided
|
||||
by the Library, but which is not otherwise based on the Library.
|
||||
Defining a subclass of a class defined by the Library is deemed a mode
|
||||
of using an interface provided by the Library.
|
||||
|
||||
A "Combined Work" is a work produced by combining or linking an
|
||||
Application with the Library. The particular version of the Library
|
||||
with which the Combined Work was made is also called the "Linked
|
||||
Version".
|
||||
|
||||
The "Minimal Corresponding Source" for a Combined Work means the
|
||||
Corresponding Source for the Combined Work, excluding any source code
|
||||
for portions of the Combined Work that, considered in isolation, are
|
||||
based on the Application, and not on the Linked Version.
|
||||
|
||||
The "Corresponding Application Code" for a Combined Work means the
|
||||
object code and/or source code for the Application, including any data
|
||||
and utility programs needed for reproducing the Combined Work from the
|
||||
Application, but excluding the System Libraries of the Combined Work.
|
||||
|
||||
1. Exception to Section 3 of the GNU GPL.
|
||||
|
||||
You may convey a covered work under sections 3 and 4 of this License
|
||||
without being bound by section 3 of the GNU GPL.
|
||||
|
||||
2. Conveying Modified Versions.
|
||||
|
||||
If you modify a copy of the Library, and, in your modifications, a
|
||||
facility refers to a function or data to be supplied by an Application
|
||||
that uses the facility (other than as an argument passed when the
|
||||
facility is invoked), then you may convey a copy of the modified
|
||||
version:
|
||||
|
||||
a) under this License, provided that you make a good faith effort to
|
||||
ensure that, in the event an Application does not supply the
|
||||
function or data, the facility still operates, and performs
|
||||
whatever part of its purpose remains meaningful, or
|
||||
|
||||
b) under the GNU GPL, with none of the additional permissions of
|
||||
this License applicable to that copy.
|
||||
|
||||
3. Object Code Incorporating Material from Library Header Files.
|
||||
|
||||
The object code form of an Application may incorporate material from
|
||||
a header file that is part of the Library. You may convey such object
|
||||
code under terms of your choice, provided that, if the incorporated
|
||||
material is not limited to numerical parameters, data structure
|
||||
layouts and accessors, or small macros, inline functions and templates
|
||||
(ten or fewer lines in length), you do both of the following:
|
||||
|
||||
a) Give prominent notice with each copy of the object code that the
|
||||
Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the object code with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
4. Combined Works.
|
||||
|
||||
You may convey a Combined Work under terms of your choice that,
|
||||
taken together, effectively do not restrict modification of the
|
||||
portions of the Library contained in the Combined Work and reverse
|
||||
engineering for debugging such modifications, if you also do each of
|
||||
the following:
|
||||
|
||||
a) Give prominent notice with each copy of the Combined Work that
|
||||
the Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the Combined Work with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
c) For a Combined Work that displays copyright notices during
|
||||
execution, include the copyright notice for the Library among
|
||||
these notices, as well as a reference directing the user to the
|
||||
copies of the GNU GPL and this license document.
|
||||
|
||||
d) Do one of the following:
|
||||
|
||||
0) Convey the Minimal Corresponding Source under the terms of this
|
||||
License, and the Corresponding Application Code in a form
|
||||
suitable for, and under terms that permit, the user to
|
||||
recombine or relink the Application with a modified version of
|
||||
the Linked Version to produce a modified Combined Work, in the
|
||||
manner specified by section 6 of the GNU GPL for conveying
|
||||
Corresponding Source.
|
||||
|
||||
1) Use a suitable shared library mechanism for linking with the
|
||||
Library. A suitable mechanism is one that (a) uses at run time
|
||||
a copy of the Library already present on the user's computer
|
||||
system, and (b) will operate properly with a modified version
|
||||
of the Library that is interface-compatible with the Linked
|
||||
Version.
|
||||
|
||||
e) Provide Installation Information, but only if you would otherwise
|
||||
be required to provide such information under section 6 of the
|
||||
GNU GPL, and only to the extent that such information is
|
||||
necessary to install and execute a modified version of the
|
||||
Combined Work produced by recombining or relinking the
|
||||
Application with a modified version of the Linked Version. (If
|
||||
you use option 4d0, the Installation Information must accompany
|
||||
the Minimal Corresponding Source and Corresponding Application
|
||||
Code. If you use option 4d1, you must provide the Installation
|
||||
Information in the manner specified by section 6 of the GNU GPL
|
||||
for conveying Corresponding Source.)
|
||||
|
||||
5. Combined Libraries.
|
||||
|
||||
You may place library facilities that are a work based on the
|
||||
Library side by side in a single library together with other library
|
||||
facilities that are not Applications and are not covered by this
|
||||
License, and convey such a combined library under terms of your
|
||||
choice, if you do both of the following:
|
||||
|
||||
a) Accompany the combined library with a copy of the same work based
|
||||
on the Library, uncombined with any other library facilities,
|
||||
conveyed under the terms of this License.
|
||||
|
||||
b) Give prominent notice with the combined library that part of it
|
||||
is a work based on the Library, and explaining where to find the
|
||||
accompanying uncombined form of the same work.
|
||||
|
||||
6. Revised Versions of the GNU Lesser General Public License.
|
||||
|
||||
The Free Software Foundation may publish revised and/or new versions
|
||||
of the GNU Lesser General Public License from time to time. Such new
|
||||
versions will be similar in spirit to the present version, but may
|
||||
differ in detail to address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the
|
||||
Library as you received it specifies that a certain numbered version
|
||||
of the GNU Lesser General Public License "or any later version"
|
||||
applies to it, you have the option of following the terms and
|
||||
conditions either of that published version or of any later version
|
||||
published by the Free Software Foundation. If the Library as you
|
||||
received it does not specify a version number of the GNU Lesser
|
||||
General Public License, you may choose any version of the GNU Lesser
|
||||
General Public License ever published by the Free Software Foundation.
|
||||
|
||||
If the Library as you received it specifies that a proxy can decide
|
||||
whether future versions of the GNU Lesser General Public License shall
|
||||
apply, that proxy's public statement of acceptance of any version is
|
||||
permanent authorization for you to choose that version for the
|
||||
Library.
|
||||
|
||||
= vendor/github.com/juju/ratelimit/LICENSE 2d1c30374313ae40df7772dc92ef9fd5 -
|
||||
================================================================================
|
||||
|
||||
|
||||
================================================================================
|
||||
= vendor/github.com/kardianos/osext licensed under: =
|
||||
|
||||
|
|
|
@ -220,6 +220,7 @@ pkg/util/limitwriter
|
|||
pkg/util/logs
|
||||
pkg/util/maps
|
||||
pkg/util/metrics
|
||||
pkg/util/ratelimit
|
||||
pkg/util/replicaset
|
||||
pkg/util/validation/field
|
||||
pkg/util/workqueue
|
||||
|
|
|
@ -20,7 +20,7 @@ go_library(
|
|||
deps = [
|
||||
"//pkg/util/clock:go_default_library",
|
||||
"//pkg/util/integer:go_default_library",
|
||||
"//vendor:github.com/juju/ratelimit",
|
||||
"//pkg/util/ratelimit:go_default_library",
|
||||
],
|
||||
)
|
||||
|
||||
|
|
|
@ -19,7 +19,7 @@ package flowcontrol
|
|||
import (
|
||||
"sync"
|
||||
|
||||
"github.com/juju/ratelimit"
|
||||
"k8s.io/kubernetes/pkg/util/ratelimit"
|
||||
)
|
||||
|
||||
type RateLimiter interface {
|
||||
|
|
|
@ -0,0 +1,25 @@
|
|||
package(default_visibility = ["//visibility:public"])
|
||||
|
||||
licenses(["notice"])
|
||||
|
||||
load(
|
||||
"@io_bazel_rules_go//go:def.bzl",
|
||||
"go_binary",
|
||||
"go_library",
|
||||
"go_test",
|
||||
"cgo_library",
|
||||
)
|
||||
|
||||
go_library(
|
||||
name = "go_default_library",
|
||||
srcs = ["bucket.go"],
|
||||
tags = ["automanaged"],
|
||||
)
|
||||
|
||||
go_test(
|
||||
name = "go_default_test",
|
||||
srcs = ["bucket_test.go"],
|
||||
library = "go_default_library",
|
||||
tags = ["automanaged"],
|
||||
deps = [],
|
||||
)
|
|
@ -0,0 +1,170 @@
|
|||
/*
|
||||
Copyright 2016 The Kubernetes Authors.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package ratelimit
|
||||
|
||||
import (
|
||||
"math"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// Bucket models a token bucket
|
||||
type Bucket struct {
|
||||
unitsPerNano float64
|
||||
nanosPerUnit float64
|
||||
capacity int64
|
||||
|
||||
mutex sync.Mutex
|
||||
available int64
|
||||
lastRefill int64
|
||||
// fractionalAvailable "buffers" any amounts that flowed into the bucket smaller than one unit
|
||||
// This lets us retain precision even with pathological refill rates like (1E9 + 1) per second
|
||||
fractionalAvailable float64
|
||||
}
|
||||
|
||||
// NewBucketWithRate creates a new token bucket, with maximum capacity = initial capacity, and a refill rate of qps
|
||||
// We use floats for refill calculations, which introduces the possibility of truncation and rounding errors.
|
||||
// For "sensible" qps values though, is is acceptable: jbeda did some tests here https://play.golang.org/p/LSKUOGz2LG
|
||||
func NewBucketWithRate(qps float64, capacity int64) *Bucket {
|
||||
unitsPerNano := qps / 1E9
|
||||
nanosPerUnit := 1E9 / qps
|
||||
b := &Bucket{
|
||||
unitsPerNano: unitsPerNano,
|
||||
nanosPerUnit: nanosPerUnit,
|
||||
capacity: capacity,
|
||||
available: capacity,
|
||||
lastRefill: time.Now().UnixNano(),
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// Take takes n units from the bucket, reducing the available quantity even below zero,
|
||||
// but then returns the amount of time we should wait
|
||||
func (b *Bucket) Take(n int64) time.Duration {
|
||||
b.mutex.Lock()
|
||||
defer b.mutex.Unlock()
|
||||
|
||||
var d time.Duration
|
||||
if b.available >= n {
|
||||
// Fast path when bucket has sufficient availability before refilling
|
||||
} else {
|
||||
b.refill()
|
||||
|
||||
if b.available < n {
|
||||
deficit := n - b.available
|
||||
d = time.Duration(int64(float64(deficit) * b.nanosPerUnit))
|
||||
}
|
||||
}
|
||||
|
||||
b.available -= n
|
||||
|
||||
return d
|
||||
}
|
||||
|
||||
// TakeAvailable immediately takes whatever quantity is available, up to max
|
||||
func (b *Bucket) TakeAvailable(max int64) int64 {
|
||||
b.mutex.Lock()
|
||||
defer b.mutex.Unlock()
|
||||
|
||||
var took int64
|
||||
if b.available >= max {
|
||||
// Fast path when bucket has sufficient availability before refilling
|
||||
took = max
|
||||
} else {
|
||||
b.refill()
|
||||
|
||||
took = b.available
|
||||
|
||||
if took < 0 {
|
||||
took = 0
|
||||
} else if took > max {
|
||||
took = max
|
||||
}
|
||||
}
|
||||
|
||||
if took > 0 {
|
||||
b.available -= took
|
||||
}
|
||||
|
||||
return took
|
||||
}
|
||||
|
||||
// Wait combines a call to Take with a sleep call
|
||||
func (b *Bucket) Wait(n int64) {
|
||||
d := b.Take(n)
|
||||
if d != 0 {
|
||||
time.Sleep(d)
|
||||
}
|
||||
}
|
||||
|
||||
// Capacity returns the maximum capacity of the bucket
|
||||
func (b *Bucket) Capacity() int64 {
|
||||
return b.capacity
|
||||
}
|
||||
|
||||
// Available returns the quantity available in the bucket (which may be negative), but does not take it.
|
||||
// This function is for diagnostic / informational purposes only - the returned capacity may immediately
|
||||
// be inaccurate if another thread is operating on the bucket concurrently.
|
||||
func (b *Bucket) Available() int64 {
|
||||
b.mutex.Lock()
|
||||
defer b.mutex.Unlock()
|
||||
|
||||
b.refill()
|
||||
|
||||
return b.available
|
||||
}
|
||||
|
||||
// refill replenishes the bucket based on elapsed time; mutex must be held
|
||||
func (b *Bucket) refill() {
|
||||
// Note that we really want a monotonic clock here, but go says no:
|
||||
// https://github.com/golang/go/issues/12914
|
||||
now := time.Now().UnixNano()
|
||||
|
||||
b.refillAtTimestamp(now)
|
||||
}
|
||||
|
||||
// refillAtTimestamp is the logic of the refill function, for testing
|
||||
func (b *Bucket) refillAtTimestamp(now int64) {
|
||||
nanosSinceLastRefill := now - b.lastRefill
|
||||
if nanosSinceLastRefill <= 0 {
|
||||
// we really want monotonic
|
||||
return
|
||||
}
|
||||
|
||||
// Compute units that have flowed into bucket
|
||||
refillFloat := (float64(nanosSinceLastRefill) * b.unitsPerNano) + b.fractionalAvailable
|
||||
if refillFloat > float64(b.capacity) {
|
||||
// float64 > MaxInt64 can be converted to negative int64; side step this
|
||||
b.available = b.capacity
|
||||
|
||||
// Don't worry about the fractional units with huge refill rates
|
||||
} else {
|
||||
whole, fraction := math.Modf(refillFloat)
|
||||
refill := int64(whole)
|
||||
b.fractionalAvailable = fraction
|
||||
if refill != 0 {
|
||||
// Refill with overflow
|
||||
b.available += refill
|
||||
if b.available >= b.capacity {
|
||||
b.available = b.capacity
|
||||
b.fractionalAvailable = 0
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
b.lastRefill = now
|
||||
}
|
|
@ -0,0 +1,179 @@
|
|||
/*
|
||||
Copyright 2016 The Kubernetes Authors.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package ratelimit
|
||||
|
||||
import (
|
||||
"testing"
|
||||
"time"
|
||||
)
|
||||
|
||||
func TestSimpleExhaustion(t *testing.T) {
|
||||
capacity := int64(3)
|
||||
b := NewBucketWithRate(1, capacity)
|
||||
|
||||
// Empty the bucket
|
||||
for i := int64(0); i < capacity; i++ {
|
||||
testAvailable(t, b, capacity-i)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
}
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// A take on an empty bucket should incur a delay
|
||||
testTakeDelay(t, b, 1, 1*time.Second, 100*time.Millisecond)
|
||||
testAvailable(t, b, -1)
|
||||
}
|
||||
|
||||
func TestRefill(t *testing.T) {
|
||||
capacity := int64(3)
|
||||
b := NewBucketWithRate(1, capacity)
|
||||
clock := b.lastRefill
|
||||
|
||||
// Empty the bucket
|
||||
testAvailable(t, b, capacity)
|
||||
for i := int64(0); i < capacity; i++ {
|
||||
testTakeNoDelay(t, b, 1)
|
||||
}
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// In one second, one unit should be refilled
|
||||
clock += time.Second.Nanoseconds()
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// Partial refill periods don't result in lost time
|
||||
for i := 0; i < 4; i++ {
|
||||
clock += time.Millisecond.Nanoseconds() * 200
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
clock += time.Millisecond.Nanoseconds() * 200
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
|
||||
// TestSlowRefillRate checks we don't have problems with tiny refill rates
|
||||
func TestSlowRefillRate(t *testing.T) {
|
||||
for _, capacity := range []int64{int64(1), int64(1E18)} {
|
||||
b := NewBucketWithRate(1E-9, capacity)
|
||||
clock := b.lastRefill
|
||||
|
||||
// Empty the bucket
|
||||
testTakeNoDelay(t, b, b.available)
|
||||
|
||||
// In one second, should refill nothing
|
||||
clock += time.Second.Nanoseconds()
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// We need to have 1E18 nanos to see any refill
|
||||
clock += 1E18
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
}
|
||||
|
||||
// TestFastRefillRate checks for refill rates that are around 1 / ns (our granularity)
|
||||
func TestFastRefillRate(t *testing.T) {
|
||||
for _, capacity := range []int64{int64(1), int64(1E18)} {
|
||||
b := NewBucketWithRate(1E9, capacity)
|
||||
|
||||
// Empty the bucket
|
||||
testTakeNoDelay(t, b, b.available)
|
||||
|
||||
// In one nanosecond, should refill exactly one unit
|
||||
clock := b.lastRefill + 1
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
}
|
||||
|
||||
// TestRefillRatePrecision checks for rounding errors
|
||||
func TestRefillRatePrecision(t *testing.T) {
|
||||
capacity := int64(1E18)
|
||||
b := NewBucketWithRate(1+1E9, capacity)
|
||||
|
||||
// Empty the bucket
|
||||
testTakeNoDelay(t, b, b.available)
|
||||
|
||||
// In one nanosecond, should refill exactly one unit
|
||||
clock := b.lastRefill + 1
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1)
|
||||
testTakeNoDelay(t, b, 1)
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// In one second, should refill the 1 extra also
|
||||
clock += 1E9
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, 1000000001)
|
||||
testTakeNoDelay(t, b, 1000000001)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
|
||||
// TestSlowRefillRate checks we don't have problems with ridiculously high refill rates
|
||||
func TestHugeRefillRate(t *testing.T) {
|
||||
for _, capacity := range []int64{int64(1), int64(1E18)} {
|
||||
b := NewBucketWithRate(1E27, capacity)
|
||||
|
||||
// Empty the bucket
|
||||
testTakeNoDelay(t, b, b.available)
|
||||
|
||||
// In one nanosecond, should refill to capacity
|
||||
clock := b.lastRefill + 1
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, capacity)
|
||||
testTakeNoDelay(t, b, capacity)
|
||||
testAvailable(t, b, 0)
|
||||
|
||||
// In one second, should refill to capacity, but with huge overflow that must be discarded
|
||||
clock += time.Second.Nanoseconds()
|
||||
b.refillAtTimestamp(clock)
|
||||
testAvailable(t, b, capacity)
|
||||
testTakeNoDelay(t, b, capacity)
|
||||
testAvailable(t, b, 0)
|
||||
}
|
||||
}
|
||||
|
||||
func testAvailable(t *testing.T, b *Bucket, expected int64) {
|
||||
available := b.available
|
||||
if available != expected {
|
||||
t.Errorf("unexpected available; expected=%d, actual=%d", expected, available)
|
||||
}
|
||||
}
|
||||
|
||||
func testTakeDelay(t *testing.T, b *Bucket, take int64, expected time.Duration, tolerance time.Duration) {
|
||||
actual := b.Take(take)
|
||||
error := expected.Nanoseconds() - actual.Nanoseconds()
|
||||
if error < 0 {
|
||||
error = -error
|
||||
}
|
||||
if error > tolerance.Nanoseconds() {
|
||||
t.Errorf("unexpected delay on take(%d); expected=%d, actual=%d", take, expected, actual)
|
||||
}
|
||||
}
|
||||
|
||||
func testTakeNoDelay(t *testing.T, b *Bucket, take int64) {
|
||||
testTakeDelay(t, b, take, 0, 0)
|
||||
}
|
|
@ -25,8 +25,8 @@ go_library(
|
|||
tags = ["automanaged"],
|
||||
deps = [
|
||||
"//pkg/util/clock:go_default_library",
|
||||
"//pkg/util/ratelimit:go_default_library",
|
||||
"//pkg/util/runtime:go_default_library",
|
||||
"//vendor:github.com/juju/ratelimit",
|
||||
],
|
||||
)
|
||||
|
||||
|
|
|
@ -21,7 +21,7 @@ import (
|
|||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/juju/ratelimit"
|
||||
"k8s.io/kubernetes/pkg/util/ratelimit"
|
||||
)
|
||||
|
||||
type RateLimiter interface {
|
||||
|
@ -35,7 +35,7 @@ type RateLimiter interface {
|
|||
}
|
||||
|
||||
// DefaultControllerRateLimiter is a no-arg constructor for a default rate limiter for a workqueue. It has
|
||||
// both overall and per-item rate limitting. The overall is a token bucket and the per-item is exponential
|
||||
// both overall and per-item rate limiting. The overall is a token bucket and the per-item is exponential
|
||||
func DefaultControllerRateLimiter() RateLimiter {
|
||||
return NewMaxOfRateLimiter(
|
||||
NewItemExponentialFailureRateLimiter(5*time.Millisecond, 1000*time.Second),
|
||||
|
|
|
@ -161,10 +161,6 @@
|
|||
"ImportPath": "github.com/jonboulle/clockwork",
|
||||
"Rev": "72f9bd7c4e0c2a40055ab3d0f09654f730cce982"
|
||||
},
|
||||
{
|
||||
"ImportPath": "github.com/juju/ratelimit",
|
||||
"Rev": "77ed1c8a01217656d2080ad51981f6e99adaa177"
|
||||
},
|
||||
{
|
||||
"ImportPath": "github.com/mailru/easyjson/buffer",
|
||||
"Rev": "d5b7844b561a7bc640052f1b935f7b800330d7e0"
|
||||
|
|
|
@ -1,191 +0,0 @@
|
|||
All files in this repository are licensed as follows. If you contribute
|
||||
to this repository, it is assumed that you license your contribution
|
||||
under the same license unless you state otherwise.
|
||||
|
||||
All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file.
|
||||
|
||||
This software is licensed under the LGPLv3, included below.
|
||||
|
||||
As a special exception to the GNU Lesser General Public License version 3
|
||||
("LGPL3"), the copyright holders of this Library give you permission to
|
||||
convey to a third party a Combined Work that links statically or dynamically
|
||||
to this Library without providing any Minimal Corresponding Source or
|
||||
Minimal Application Code as set out in 4d or providing the installation
|
||||
information set out in section 4e, provided that you comply with the other
|
||||
provisions of LGPL3 and provided that you meet, for the Application the
|
||||
terms and conditions of the license(s) which apply to the Application.
|
||||
|
||||
Except as stated in this special exception, the provisions of LGPL3 will
|
||||
continue to comply in full to this Library. If you modify this Library, you
|
||||
may apply this exception to your version of this Library, but you are not
|
||||
obliged to do so. If you do not wish to do so, delete this exception
|
||||
statement from your version. This exception does not (and cannot) modify any
|
||||
license terms which apply to the Application, with which you must still
|
||||
comply.
|
||||
|
||||
|
||||
GNU LESSER GENERAL PUBLIC LICENSE
|
||||
Version 3, 29 June 2007
|
||||
|
||||
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
|
||||
This version of the GNU Lesser General Public License incorporates
|
||||
the terms and conditions of version 3 of the GNU General Public
|
||||
License, supplemented by the additional permissions listed below.
|
||||
|
||||
0. Additional Definitions.
|
||||
|
||||
As used herein, "this License" refers to version 3 of the GNU Lesser
|
||||
General Public License, and the "GNU GPL" refers to version 3 of the GNU
|
||||
General Public License.
|
||||
|
||||
"The Library" refers to a covered work governed by this License,
|
||||
other than an Application or a Combined Work as defined below.
|
||||
|
||||
An "Application" is any work that makes use of an interface provided
|
||||
by the Library, but which is not otherwise based on the Library.
|
||||
Defining a subclass of a class defined by the Library is deemed a mode
|
||||
of using an interface provided by the Library.
|
||||
|
||||
A "Combined Work" is a work produced by combining or linking an
|
||||
Application with the Library. The particular version of the Library
|
||||
with which the Combined Work was made is also called the "Linked
|
||||
Version".
|
||||
|
||||
The "Minimal Corresponding Source" for a Combined Work means the
|
||||
Corresponding Source for the Combined Work, excluding any source code
|
||||
for portions of the Combined Work that, considered in isolation, are
|
||||
based on the Application, and not on the Linked Version.
|
||||
|
||||
The "Corresponding Application Code" for a Combined Work means the
|
||||
object code and/or source code for the Application, including any data
|
||||
and utility programs needed for reproducing the Combined Work from the
|
||||
Application, but excluding the System Libraries of the Combined Work.
|
||||
|
||||
1. Exception to Section 3 of the GNU GPL.
|
||||
|
||||
You may convey a covered work under sections 3 and 4 of this License
|
||||
without being bound by section 3 of the GNU GPL.
|
||||
|
||||
2. Conveying Modified Versions.
|
||||
|
||||
If you modify a copy of the Library, and, in your modifications, a
|
||||
facility refers to a function or data to be supplied by an Application
|
||||
that uses the facility (other than as an argument passed when the
|
||||
facility is invoked), then you may convey a copy of the modified
|
||||
version:
|
||||
|
||||
a) under this License, provided that you make a good faith effort to
|
||||
ensure that, in the event an Application does not supply the
|
||||
function or data, the facility still operates, and performs
|
||||
whatever part of its purpose remains meaningful, or
|
||||
|
||||
b) under the GNU GPL, with none of the additional permissions of
|
||||
this License applicable to that copy.
|
||||
|
||||
3. Object Code Incorporating Material from Library Header Files.
|
||||
|
||||
The object code form of an Application may incorporate material from
|
||||
a header file that is part of the Library. You may convey such object
|
||||
code under terms of your choice, provided that, if the incorporated
|
||||
material is not limited to numerical parameters, data structure
|
||||
layouts and accessors, or small macros, inline functions and templates
|
||||
(ten or fewer lines in length), you do both of the following:
|
||||
|
||||
a) Give prominent notice with each copy of the object code that the
|
||||
Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the object code with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
4. Combined Works.
|
||||
|
||||
You may convey a Combined Work under terms of your choice that,
|
||||
taken together, effectively do not restrict modification of the
|
||||
portions of the Library contained in the Combined Work and reverse
|
||||
engineering for debugging such modifications, if you also do each of
|
||||
the following:
|
||||
|
||||
a) Give prominent notice with each copy of the Combined Work that
|
||||
the Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the Combined Work with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
c) For a Combined Work that displays copyright notices during
|
||||
execution, include the copyright notice for the Library among
|
||||
these notices, as well as a reference directing the user to the
|
||||
copies of the GNU GPL and this license document.
|
||||
|
||||
d) Do one of the following:
|
||||
|
||||
0) Convey the Minimal Corresponding Source under the terms of this
|
||||
License, and the Corresponding Application Code in a form
|
||||
suitable for, and under terms that permit, the user to
|
||||
recombine or relink the Application with a modified version of
|
||||
the Linked Version to produce a modified Combined Work, in the
|
||||
manner specified by section 6 of the GNU GPL for conveying
|
||||
Corresponding Source.
|
||||
|
||||
1) Use a suitable shared library mechanism for linking with the
|
||||
Library. A suitable mechanism is one that (a) uses at run time
|
||||
a copy of the Library already present on the user's computer
|
||||
system, and (b) will operate properly with a modified version
|
||||
of the Library that is interface-compatible with the Linked
|
||||
Version.
|
||||
|
||||
e) Provide Installation Information, but only if you would otherwise
|
||||
be required to provide such information under section 6 of the
|
||||
GNU GPL, and only to the extent that such information is
|
||||
necessary to install and execute a modified version of the
|
||||
Combined Work produced by recombining or relinking the
|
||||
Application with a modified version of the Linked Version. (If
|
||||
you use option 4d0, the Installation Information must accompany
|
||||
the Minimal Corresponding Source and Corresponding Application
|
||||
Code. If you use option 4d1, you must provide the Installation
|
||||
Information in the manner specified by section 6 of the GNU GPL
|
||||
for conveying Corresponding Source.)
|
||||
|
||||
5. Combined Libraries.
|
||||
|
||||
You may place library facilities that are a work based on the
|
||||
Library side by side in a single library together with other library
|
||||
facilities that are not Applications and are not covered by this
|
||||
License, and convey such a combined library under terms of your
|
||||
choice, if you do both of the following:
|
||||
|
||||
a) Accompany the combined library with a copy of the same work based
|
||||
on the Library, uncombined with any other library facilities,
|
||||
conveyed under the terms of this License.
|
||||
|
||||
b) Give prominent notice with the combined library that part of it
|
||||
is a work based on the Library, and explaining where to find the
|
||||
accompanying uncombined form of the same work.
|
||||
|
||||
6. Revised Versions of the GNU Lesser General Public License.
|
||||
|
||||
The Free Software Foundation may publish revised and/or new versions
|
||||
of the GNU Lesser General Public License from time to time. Such new
|
||||
versions will be similar in spirit to the present version, but may
|
||||
differ in detail to address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the
|
||||
Library as you received it specifies that a certain numbered version
|
||||
of the GNU Lesser General Public License "or any later version"
|
||||
applies to it, you have the option of following the terms and
|
||||
conditions either of that published version or of any later version
|
||||
published by the Free Software Foundation. If the Library as you
|
||||
received it does not specify a version number of the GNU Lesser
|
||||
General Public License, you may choose any version of the GNU Lesser
|
||||
General Public License ever published by the Free Software Foundation.
|
||||
|
||||
If the Library as you received it specifies that a proxy can decide
|
||||
whether future versions of the GNU Lesser General Public License shall
|
||||
apply, that proxy's public statement of acceptance of any version is
|
||||
permanent authorization for you to choose that version for the
|
||||
Library.
|
|
@ -1,117 +0,0 @@
|
|||
# ratelimit
|
||||
--
|
||||
import "github.com/juju/ratelimit"
|
||||
|
||||
The ratelimit package provides an efficient token bucket implementation. See
|
||||
http://en.wikipedia.org/wiki/Token_bucket.
|
||||
|
||||
## Usage
|
||||
|
||||
#### func Reader
|
||||
|
||||
```go
|
||||
func Reader(r io.Reader, bucket *Bucket) io.Reader
|
||||
```
|
||||
Reader returns a reader that is rate limited by the given token bucket. Each
|
||||
token in the bucket represents one byte.
|
||||
|
||||
#### func Writer
|
||||
|
||||
```go
|
||||
func Writer(w io.Writer, bucket *Bucket) io.Writer
|
||||
```
|
||||
Writer returns a writer that is rate limited by the given token bucket. Each
|
||||
token in the bucket represents one byte.
|
||||
|
||||
#### type Bucket
|
||||
|
||||
```go
|
||||
type Bucket struct {
|
||||
}
|
||||
```
|
||||
|
||||
Bucket represents a token bucket that fills at a predetermined rate. Methods on
|
||||
Bucket may be called concurrently.
|
||||
|
||||
#### func NewBucket
|
||||
|
||||
```go
|
||||
func NewBucket(fillInterval time.Duration, capacity int64) *Bucket
|
||||
```
|
||||
NewBucket returns a new token bucket that fills at the rate of one token every
|
||||
fillInterval, up to the given maximum capacity. Both arguments must be positive.
|
||||
The bucket is initially full.
|
||||
|
||||
#### func NewBucketWithQuantum
|
||||
|
||||
```go
|
||||
func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket
|
||||
```
|
||||
NewBucketWithQuantum is similar to NewBucket, but allows the specification of
|
||||
the quantum size - quantum tokens are added every fillInterval.
|
||||
|
||||
#### func NewBucketWithRate
|
||||
|
||||
```go
|
||||
func NewBucketWithRate(rate float64, capacity int64) *Bucket
|
||||
```
|
||||
NewBucketWithRate returns a token bucket that fills the bucket at the rate of
|
||||
rate tokens per second up to the given maximum capacity. Because of limited
|
||||
clock resolution, at high rates, the actual rate may be up to 1% different from
|
||||
the specified rate.
|
||||
|
||||
#### func (*Bucket) Rate
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Rate() float64
|
||||
```
|
||||
Rate returns the fill rate of the bucket, in tokens per second.
|
||||
|
||||
#### func (*Bucket) Take
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Take(count int64) time.Duration
|
||||
```
|
||||
Take takes count tokens from the bucket without blocking. It returns the time
|
||||
that the caller should wait until the tokens are actually available.
|
||||
|
||||
Note that if the request is irrevocable - there is no way to return tokens to
|
||||
the bucket once this method commits us to taking them.
|
||||
|
||||
#### func (*Bucket) TakeAvailable
|
||||
|
||||
```go
|
||||
func (tb *Bucket) TakeAvailable(count int64) int64
|
||||
```
|
||||
TakeAvailable takes up to count immediately available tokens from the bucket. It
|
||||
returns the number of tokens removed, or zero if there are no available tokens.
|
||||
It does not block.
|
||||
|
||||
#### func (*Bucket) TakeMaxDuration
|
||||
|
||||
```go
|
||||
func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool)
|
||||
```
|
||||
TakeMaxDuration is like Take, except that it will only take tokens from the
|
||||
bucket if the wait time for the tokens is no greater than maxWait.
|
||||
|
||||
If it would take longer than maxWait for the tokens to become available, it does
|
||||
nothing and reports false, otherwise it returns the time that the caller should
|
||||
wait until the tokens are actually available, and reports true.
|
||||
|
||||
#### func (*Bucket) Wait
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Wait(count int64)
|
||||
```
|
||||
Wait takes count tokens from the bucket, waiting until they are available.
|
||||
|
||||
#### func (*Bucket) WaitMaxDuration
|
||||
|
||||
```go
|
||||
func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool
|
||||
```
|
||||
WaitMaxDuration is like Wait except that it will only take tokens from the
|
||||
bucket if it needs to wait for no greater than maxWait. It reports whether any
|
||||
tokens have been removed from the bucket If no tokens have been removed, it
|
||||
returns immediately.
|
|
@ -1,245 +0,0 @@
|
|||
// Copyright 2014 Canonical Ltd.
|
||||
// Licensed under the LGPLv3 with static-linking exception.
|
||||
// See LICENCE file for details.
|
||||
|
||||
// The ratelimit package provides an efficient token bucket implementation
|
||||
// that can be used to limit the rate of arbitrary things.
|
||||
// See http://en.wikipedia.org/wiki/Token_bucket.
|
||||
package ratelimit
|
||||
|
||||
import (
|
||||
"math"
|
||||
"strconv"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// Bucket represents a token bucket that fills at a predetermined rate.
|
||||
// Methods on Bucket may be called concurrently.
|
||||
type Bucket struct {
|
||||
startTime time.Time
|
||||
capacity int64
|
||||
quantum int64
|
||||
fillInterval time.Duration
|
||||
|
||||
// The mutex guards the fields following it.
|
||||
mu sync.Mutex
|
||||
|
||||
// avail holds the number of available tokens
|
||||
// in the bucket, as of availTick ticks from startTime.
|
||||
// It will be negative when there are consumers
|
||||
// waiting for tokens.
|
||||
avail int64
|
||||
availTick int64
|
||||
}
|
||||
|
||||
// NewBucket returns a new token bucket that fills at the
|
||||
// rate of one token every fillInterval, up to the given
|
||||
// maximum capacity. Both arguments must be
|
||||
// positive. The bucket is initially full.
|
||||
func NewBucket(fillInterval time.Duration, capacity int64) *Bucket {
|
||||
return NewBucketWithQuantum(fillInterval, capacity, 1)
|
||||
}
|
||||
|
||||
// rateMargin specifes the allowed variance of actual
|
||||
// rate from specified rate. 1% seems reasonable.
|
||||
const rateMargin = 0.01
|
||||
|
||||
// NewBucketWithRate returns a token bucket that fills the bucket
|
||||
// at the rate of rate tokens per second up to the given
|
||||
// maximum capacity. Because of limited clock resolution,
|
||||
// at high rates, the actual rate may be up to 1% different from the
|
||||
// specified rate.
|
||||
func NewBucketWithRate(rate float64, capacity int64) *Bucket {
|
||||
for quantum := int64(1); quantum < 1<<50; quantum = nextQuantum(quantum) {
|
||||
fillInterval := time.Duration(1e9 * float64(quantum) / rate)
|
||||
if fillInterval <= 0 {
|
||||
continue
|
||||
}
|
||||
tb := NewBucketWithQuantum(fillInterval, capacity, quantum)
|
||||
if diff := math.Abs(tb.Rate() - rate); diff/rate <= rateMargin {
|
||||
return tb
|
||||
}
|
||||
}
|
||||
panic("cannot find suitable quantum for " + strconv.FormatFloat(rate, 'g', -1, 64))
|
||||
}
|
||||
|
||||
// nextQuantum returns the next quantum to try after q.
|
||||
// We grow the quantum exponentially, but slowly, so we
|
||||
// get a good fit in the lower numbers.
|
||||
func nextQuantum(q int64) int64 {
|
||||
q1 := q * 11 / 10
|
||||
if q1 == q {
|
||||
q1++
|
||||
}
|
||||
return q1
|
||||
}
|
||||
|
||||
// NewBucketWithQuantum is similar to NewBucket, but allows
|
||||
// the specification of the quantum size - quantum tokens
|
||||
// are added every fillInterval.
|
||||
func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket {
|
||||
if fillInterval <= 0 {
|
||||
panic("token bucket fill interval is not > 0")
|
||||
}
|
||||
if capacity <= 0 {
|
||||
panic("token bucket capacity is not > 0")
|
||||
}
|
||||
if quantum <= 0 {
|
||||
panic("token bucket quantum is not > 0")
|
||||
}
|
||||
return &Bucket{
|
||||
startTime: time.Now(),
|
||||
capacity: capacity,
|
||||
quantum: quantum,
|
||||
avail: capacity,
|
||||
fillInterval: fillInterval,
|
||||
}
|
||||
}
|
||||
|
||||
// Wait takes count tokens from the bucket, waiting until they are
|
||||
// available.
|
||||
func (tb *Bucket) Wait(count int64) {
|
||||
if d := tb.Take(count); d > 0 {
|
||||
time.Sleep(d)
|
||||
}
|
||||
}
|
||||
|
||||
// WaitMaxDuration is like Wait except that it will
|
||||
// only take tokens from the bucket if it needs to wait
|
||||
// for no greater than maxWait. It reports whether
|
||||
// any tokens have been removed from the bucket
|
||||
// If no tokens have been removed, it returns immediately.
|
||||
func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool {
|
||||
d, ok := tb.TakeMaxDuration(count, maxWait)
|
||||
if d > 0 {
|
||||
time.Sleep(d)
|
||||
}
|
||||
return ok
|
||||
}
|
||||
|
||||
const infinityDuration time.Duration = 0x7fffffffffffffff
|
||||
|
||||
// Take takes count tokens from the bucket without blocking. It returns
|
||||
// the time that the caller should wait until the tokens are actually
|
||||
// available.
|
||||
//
|
||||
// Note that if the request is irrevocable - there is no way to return
|
||||
// tokens to the bucket once this method commits us to taking them.
|
||||
func (tb *Bucket) Take(count int64) time.Duration {
|
||||
d, _ := tb.take(time.Now(), count, infinityDuration)
|
||||
return d
|
||||
}
|
||||
|
||||
// TakeMaxDuration is like Take, except that
|
||||
// it will only take tokens from the bucket if the wait
|
||||
// time for the tokens is no greater than maxWait.
|
||||
//
|
||||
// If it would take longer than maxWait for the tokens
|
||||
// to become available, it does nothing and reports false,
|
||||
// otherwise it returns the time that the caller should
|
||||
// wait until the tokens are actually available, and reports
|
||||
// true.
|
||||
func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool) {
|
||||
return tb.take(time.Now(), count, maxWait)
|
||||
}
|
||||
|
||||
// TakeAvailable takes up to count immediately available tokens from the
|
||||
// bucket. It returns the number of tokens removed, or zero if there are
|
||||
// no available tokens. It does not block.
|
||||
func (tb *Bucket) TakeAvailable(count int64) int64 {
|
||||
return tb.takeAvailable(time.Now(), count)
|
||||
}
|
||||
|
||||
// takeAvailable is the internal version of TakeAvailable - it takes the
|
||||
// current time as an argument to enable easy testing.
|
||||
func (tb *Bucket) takeAvailable(now time.Time, count int64) int64 {
|
||||
if count <= 0 {
|
||||
return 0
|
||||
}
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
|
||||
tb.adjust(now)
|
||||
if tb.avail <= 0 {
|
||||
return 0
|
||||
}
|
||||
if count > tb.avail {
|
||||
count = tb.avail
|
||||
}
|
||||
tb.avail -= count
|
||||
return count
|
||||
}
|
||||
|
||||
// Available returns the number of available tokens. It will be negative
|
||||
// when there are consumers waiting for tokens. Note that if this
|
||||
// returns greater than zero, it does not guarantee that calls that take
|
||||
// tokens from the buffer will succeed, as the number of available
|
||||
// tokens could have changed in the meantime. This method is intended
|
||||
// primarily for metrics reporting and debugging.
|
||||
func (tb *Bucket) Available() int64 {
|
||||
return tb.available(time.Now())
|
||||
}
|
||||
|
||||
// available is the internal version of available - it takes the current time as
|
||||
// an argument to enable easy testing.
|
||||
func (tb *Bucket) available(now time.Time) int64 {
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
tb.adjust(now)
|
||||
return tb.avail
|
||||
}
|
||||
|
||||
// Capacity returns the capacity that the bucket was created with.
|
||||
func (tb *Bucket) Capacity() int64 {
|
||||
return tb.capacity
|
||||
}
|
||||
|
||||
// Rate returns the fill rate of the bucket, in tokens per second.
|
||||
func (tb *Bucket) Rate() float64 {
|
||||
return 1e9 * float64(tb.quantum) / float64(tb.fillInterval)
|
||||
}
|
||||
|
||||
// take is the internal version of Take - it takes the current time as
|
||||
// an argument to enable easy testing.
|
||||
func (tb *Bucket) take(now time.Time, count int64, maxWait time.Duration) (time.Duration, bool) {
|
||||
if count <= 0 {
|
||||
return 0, true
|
||||
}
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
|
||||
currentTick := tb.adjust(now)
|
||||
avail := tb.avail - count
|
||||
if avail >= 0 {
|
||||
tb.avail = avail
|
||||
return 0, true
|
||||
}
|
||||
// Round up the missing tokens to the nearest multiple
|
||||
// of quantum - the tokens won't be available until
|
||||
// that tick.
|
||||
endTick := currentTick + (-avail+tb.quantum-1)/tb.quantum
|
||||
endTime := tb.startTime.Add(time.Duration(endTick) * tb.fillInterval)
|
||||
waitTime := endTime.Sub(now)
|
||||
if waitTime > maxWait {
|
||||
return 0, false
|
||||
}
|
||||
tb.avail = avail
|
||||
return waitTime, true
|
||||
}
|
||||
|
||||
// adjust adjusts the current bucket capacity based on the current time.
|
||||
// It returns the current tick.
|
||||
func (tb *Bucket) adjust(now time.Time) (currentTick int64) {
|
||||
currentTick = int64(now.Sub(tb.startTime) / tb.fillInterval)
|
||||
|
||||
if tb.avail >= tb.capacity {
|
||||
return
|
||||
}
|
||||
tb.avail += (currentTick - tb.availTick) * tb.quantum
|
||||
if tb.avail > tb.capacity {
|
||||
tb.avail = tb.capacity
|
||||
}
|
||||
tb.availTick = currentTick
|
||||
return
|
||||
}
|
|
@ -1,51 +0,0 @@
|
|||
// Copyright 2014 Canonical Ltd.
|
||||
// Licensed under the LGPLv3 with static-linking exception.
|
||||
// See LICENCE file for details.
|
||||
|
||||
package ratelimit
|
||||
|
||||
import "io"
|
||||
|
||||
type reader struct {
|
||||
r io.Reader
|
||||
bucket *Bucket
|
||||
}
|
||||
|
||||
// Reader returns a reader that is rate limited by
|
||||
// the given token bucket. Each token in the bucket
|
||||
// represents one byte.
|
||||
func Reader(r io.Reader, bucket *Bucket) io.Reader {
|
||||
return &reader{
|
||||
r: r,
|
||||
bucket: bucket,
|
||||
}
|
||||
}
|
||||
|
||||
func (r *reader) Read(buf []byte) (int, error) {
|
||||
n, err := r.r.Read(buf)
|
||||
if n <= 0 {
|
||||
return n, err
|
||||
}
|
||||
r.bucket.Wait(int64(n))
|
||||
return n, err
|
||||
}
|
||||
|
||||
type writer struct {
|
||||
w io.Writer
|
||||
bucket *Bucket
|
||||
}
|
||||
|
||||
// Writer returns a reader that is rate limited by
|
||||
// the given token bucket. Each token in the bucket
|
||||
// represents one byte.
|
||||
func Writer(w io.Writer, bucket *Bucket) io.Writer {
|
||||
return &writer{
|
||||
w: w,
|
||||
bucket: bucket,
|
||||
}
|
||||
}
|
||||
|
||||
func (w *writer) Write(buf []byte) (int, error) {
|
||||
w.bucket.Wait(int64(len(buf)))
|
||||
return w.w.Write(buf)
|
||||
}
|
|
@ -19,7 +19,7 @@ package flowcontrol
|
|||
import (
|
||||
"sync"
|
||||
|
||||
"github.com/juju/ratelimit"
|
||||
"k8s.io/kubernetes/pkg/util/ratelimit"
|
||||
)
|
||||
|
||||
type RateLimiter interface {
|
||||
|
|
|
@ -802,6 +802,7 @@ k8s.io/kubernetes/pkg/util/parsers,derekwaynecarr,1
|
|||
k8s.io/kubernetes/pkg/util/procfs,roberthbailey,1
|
||||
k8s.io/kubernetes/pkg/util/proxy,cjcullen,1
|
||||
k8s.io/kubernetes/pkg/util/rand,madhusudancs,1
|
||||
k8s.io/kubernetes/pkg/util/ratelimit,justinsb,1
|
||||
k8s.io/kubernetes/pkg/util/runtime,davidopp,1
|
||||
k8s.io/kubernetes/pkg/util/sets,quinton-hoole,0
|
||||
k8s.io/kubernetes/pkg/util/slice,quinton-hoole,0
|
||||
|
|
|
|
@ -4240,15 +4240,6 @@ go_binary(
|
|||
deps = ["//vendor:github.com/jteeuwen/go-bindata"],
|
||||
)
|
||||
|
||||
go_library(
|
||||
name = "github.com/juju/ratelimit",
|
||||
srcs = [
|
||||
"github.com/juju/ratelimit/ratelimit.go",
|
||||
"github.com/juju/ratelimit/reader.go",
|
||||
],
|
||||
tags = ["automanaged"],
|
||||
)
|
||||
|
||||
go_library(
|
||||
name = "github.com/kardianos/osext",
|
||||
srcs = [
|
||||
|
@ -8053,15 +8044,6 @@ go_library(
|
|||
tags = ["automanaged"],
|
||||
)
|
||||
|
||||
go_library(
|
||||
name = "k8s.io/client-go/_vendor/github.com/juju/ratelimit",
|
||||
srcs = [
|
||||
"k8s.io/client-go/_vendor/github.com/juju/ratelimit/ratelimit.go",
|
||||
"k8s.io/client-go/_vendor/github.com/juju/ratelimit/reader.go",
|
||||
],
|
||||
tags = ["automanaged"],
|
||||
)
|
||||
|
||||
go_library(
|
||||
name = "k8s.io/client-go/_vendor/github.com/mailru/easyjson/buffer",
|
||||
srcs = ["k8s.io/client-go/_vendor/github.com/mailru/easyjson/buffer/pool.go"],
|
||||
|
@ -10764,7 +10746,7 @@ go_library(
|
|||
],
|
||||
tags = ["automanaged"],
|
||||
deps = [
|
||||
"//vendor:github.com/juju/ratelimit",
|
||||
"//pkg/util/ratelimit:go_default_library",
|
||||
"//vendor:k8s.io/client-go/pkg/util/clock",
|
||||
"//vendor:k8s.io/client-go/pkg/util/integer",
|
||||
],
|
||||
|
|
|
@ -1,191 +0,0 @@
|
|||
All files in this repository are licensed as follows. If you contribute
|
||||
to this repository, it is assumed that you license your contribution
|
||||
under the same license unless you state otherwise.
|
||||
|
||||
All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file.
|
||||
|
||||
This software is licensed under the LGPLv3, included below.
|
||||
|
||||
As a special exception to the GNU Lesser General Public License version 3
|
||||
("LGPL3"), the copyright holders of this Library give you permission to
|
||||
convey to a third party a Combined Work that links statically or dynamically
|
||||
to this Library without providing any Minimal Corresponding Source or
|
||||
Minimal Application Code as set out in 4d or providing the installation
|
||||
information set out in section 4e, provided that you comply with the other
|
||||
provisions of LGPL3 and provided that you meet, for the Application the
|
||||
terms and conditions of the license(s) which apply to the Application.
|
||||
|
||||
Except as stated in this special exception, the provisions of LGPL3 will
|
||||
continue to comply in full to this Library. If you modify this Library, you
|
||||
may apply this exception to your version of this Library, but you are not
|
||||
obliged to do so. If you do not wish to do so, delete this exception
|
||||
statement from your version. This exception does not (and cannot) modify any
|
||||
license terms which apply to the Application, with which you must still
|
||||
comply.
|
||||
|
||||
|
||||
GNU LESSER GENERAL PUBLIC LICENSE
|
||||
Version 3, 29 June 2007
|
||||
|
||||
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
|
||||
This version of the GNU Lesser General Public License incorporates
|
||||
the terms and conditions of version 3 of the GNU General Public
|
||||
License, supplemented by the additional permissions listed below.
|
||||
|
||||
0. Additional Definitions.
|
||||
|
||||
As used herein, "this License" refers to version 3 of the GNU Lesser
|
||||
General Public License, and the "GNU GPL" refers to version 3 of the GNU
|
||||
General Public License.
|
||||
|
||||
"The Library" refers to a covered work governed by this License,
|
||||
other than an Application or a Combined Work as defined below.
|
||||
|
||||
An "Application" is any work that makes use of an interface provided
|
||||
by the Library, but which is not otherwise based on the Library.
|
||||
Defining a subclass of a class defined by the Library is deemed a mode
|
||||
of using an interface provided by the Library.
|
||||
|
||||
A "Combined Work" is a work produced by combining or linking an
|
||||
Application with the Library. The particular version of the Library
|
||||
with which the Combined Work was made is also called the "Linked
|
||||
Version".
|
||||
|
||||
The "Minimal Corresponding Source" for a Combined Work means the
|
||||
Corresponding Source for the Combined Work, excluding any source code
|
||||
for portions of the Combined Work that, considered in isolation, are
|
||||
based on the Application, and not on the Linked Version.
|
||||
|
||||
The "Corresponding Application Code" for a Combined Work means the
|
||||
object code and/or source code for the Application, including any data
|
||||
and utility programs needed for reproducing the Combined Work from the
|
||||
Application, but excluding the System Libraries of the Combined Work.
|
||||
|
||||
1. Exception to Section 3 of the GNU GPL.
|
||||
|
||||
You may convey a covered work under sections 3 and 4 of this License
|
||||
without being bound by section 3 of the GNU GPL.
|
||||
|
||||
2. Conveying Modified Versions.
|
||||
|
||||
If you modify a copy of the Library, and, in your modifications, a
|
||||
facility refers to a function or data to be supplied by an Application
|
||||
that uses the facility (other than as an argument passed when the
|
||||
facility is invoked), then you may convey a copy of the modified
|
||||
version:
|
||||
|
||||
a) under this License, provided that you make a good faith effort to
|
||||
ensure that, in the event an Application does not supply the
|
||||
function or data, the facility still operates, and performs
|
||||
whatever part of its purpose remains meaningful, or
|
||||
|
||||
b) under the GNU GPL, with none of the additional permissions of
|
||||
this License applicable to that copy.
|
||||
|
||||
3. Object Code Incorporating Material from Library Header Files.
|
||||
|
||||
The object code form of an Application may incorporate material from
|
||||
a header file that is part of the Library. You may convey such object
|
||||
code under terms of your choice, provided that, if the incorporated
|
||||
material is not limited to numerical parameters, data structure
|
||||
layouts and accessors, or small macros, inline functions and templates
|
||||
(ten or fewer lines in length), you do both of the following:
|
||||
|
||||
a) Give prominent notice with each copy of the object code that the
|
||||
Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the object code with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
4. Combined Works.
|
||||
|
||||
You may convey a Combined Work under terms of your choice that,
|
||||
taken together, effectively do not restrict modification of the
|
||||
portions of the Library contained in the Combined Work and reverse
|
||||
engineering for debugging such modifications, if you also do each of
|
||||
the following:
|
||||
|
||||
a) Give prominent notice with each copy of the Combined Work that
|
||||
the Library is used in it and that the Library and its use are
|
||||
covered by this License.
|
||||
|
||||
b) Accompany the Combined Work with a copy of the GNU GPL and this license
|
||||
document.
|
||||
|
||||
c) For a Combined Work that displays copyright notices during
|
||||
execution, include the copyright notice for the Library among
|
||||
these notices, as well as a reference directing the user to the
|
||||
copies of the GNU GPL and this license document.
|
||||
|
||||
d) Do one of the following:
|
||||
|
||||
0) Convey the Minimal Corresponding Source under the terms of this
|
||||
License, and the Corresponding Application Code in a form
|
||||
suitable for, and under terms that permit, the user to
|
||||
recombine or relink the Application with a modified version of
|
||||
the Linked Version to produce a modified Combined Work, in the
|
||||
manner specified by section 6 of the GNU GPL for conveying
|
||||
Corresponding Source.
|
||||
|
||||
1) Use a suitable shared library mechanism for linking with the
|
||||
Library. A suitable mechanism is one that (a) uses at run time
|
||||
a copy of the Library already present on the user's computer
|
||||
system, and (b) will operate properly with a modified version
|
||||
of the Library that is interface-compatible with the Linked
|
||||
Version.
|
||||
|
||||
e) Provide Installation Information, but only if you would otherwise
|
||||
be required to provide such information under section 6 of the
|
||||
GNU GPL, and only to the extent that such information is
|
||||
necessary to install and execute a modified version of the
|
||||
Combined Work produced by recombining or relinking the
|
||||
Application with a modified version of the Linked Version. (If
|
||||
you use option 4d0, the Installation Information must accompany
|
||||
the Minimal Corresponding Source and Corresponding Application
|
||||
Code. If you use option 4d1, you must provide the Installation
|
||||
Information in the manner specified by section 6 of the GNU GPL
|
||||
for conveying Corresponding Source.)
|
||||
|
||||
5. Combined Libraries.
|
||||
|
||||
You may place library facilities that are a work based on the
|
||||
Library side by side in a single library together with other library
|
||||
facilities that are not Applications and are not covered by this
|
||||
License, and convey such a combined library under terms of your
|
||||
choice, if you do both of the following:
|
||||
|
||||
a) Accompany the combined library with a copy of the same work based
|
||||
on the Library, uncombined with any other library facilities,
|
||||
conveyed under the terms of this License.
|
||||
|
||||
b) Give prominent notice with the combined library that part of it
|
||||
is a work based on the Library, and explaining where to find the
|
||||
accompanying uncombined form of the same work.
|
||||
|
||||
6. Revised Versions of the GNU Lesser General Public License.
|
||||
|
||||
The Free Software Foundation may publish revised and/or new versions
|
||||
of the GNU Lesser General Public License from time to time. Such new
|
||||
versions will be similar in spirit to the present version, but may
|
||||
differ in detail to address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the
|
||||
Library as you received it specifies that a certain numbered version
|
||||
of the GNU Lesser General Public License "or any later version"
|
||||
applies to it, you have the option of following the terms and
|
||||
conditions either of that published version or of any later version
|
||||
published by the Free Software Foundation. If the Library as you
|
||||
received it does not specify a version number of the GNU Lesser
|
||||
General Public License, you may choose any version of the GNU Lesser
|
||||
General Public License ever published by the Free Software Foundation.
|
||||
|
||||
If the Library as you received it specifies that a proxy can decide
|
||||
whether future versions of the GNU Lesser General Public License shall
|
||||
apply, that proxy's public statement of acceptance of any version is
|
||||
permanent authorization for you to choose that version for the
|
||||
Library.
|
|
@ -1,117 +0,0 @@
|
|||
# ratelimit
|
||||
--
|
||||
import "github.com/juju/ratelimit"
|
||||
|
||||
The ratelimit package provides an efficient token bucket implementation. See
|
||||
http://en.wikipedia.org/wiki/Token_bucket.
|
||||
|
||||
## Usage
|
||||
|
||||
#### func Reader
|
||||
|
||||
```go
|
||||
func Reader(r io.Reader, bucket *Bucket) io.Reader
|
||||
```
|
||||
Reader returns a reader that is rate limited by the given token bucket. Each
|
||||
token in the bucket represents one byte.
|
||||
|
||||
#### func Writer
|
||||
|
||||
```go
|
||||
func Writer(w io.Writer, bucket *Bucket) io.Writer
|
||||
```
|
||||
Writer returns a writer that is rate limited by the given token bucket. Each
|
||||
token in the bucket represents one byte.
|
||||
|
||||
#### type Bucket
|
||||
|
||||
```go
|
||||
type Bucket struct {
|
||||
}
|
||||
```
|
||||
|
||||
Bucket represents a token bucket that fills at a predetermined rate. Methods on
|
||||
Bucket may be called concurrently.
|
||||
|
||||
#### func NewBucket
|
||||
|
||||
```go
|
||||
func NewBucket(fillInterval time.Duration, capacity int64) *Bucket
|
||||
```
|
||||
NewBucket returns a new token bucket that fills at the rate of one token every
|
||||
fillInterval, up to the given maximum capacity. Both arguments must be positive.
|
||||
The bucket is initially full.
|
||||
|
||||
#### func NewBucketWithQuantum
|
||||
|
||||
```go
|
||||
func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket
|
||||
```
|
||||
NewBucketWithQuantum is similar to NewBucket, but allows the specification of
|
||||
the quantum size - quantum tokens are added every fillInterval.
|
||||
|
||||
#### func NewBucketWithRate
|
||||
|
||||
```go
|
||||
func NewBucketWithRate(rate float64, capacity int64) *Bucket
|
||||
```
|
||||
NewBucketWithRate returns a token bucket that fills the bucket at the rate of
|
||||
rate tokens per second up to the given maximum capacity. Because of limited
|
||||
clock resolution, at high rates, the actual rate may be up to 1% different from
|
||||
the specified rate.
|
||||
|
||||
#### func (*Bucket) Rate
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Rate() float64
|
||||
```
|
||||
Rate returns the fill rate of the bucket, in tokens per second.
|
||||
|
||||
#### func (*Bucket) Take
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Take(count int64) time.Duration
|
||||
```
|
||||
Take takes count tokens from the bucket without blocking. It returns the time
|
||||
that the caller should wait until the tokens are actually available.
|
||||
|
||||
Note that if the request is irrevocable - there is no way to return tokens to
|
||||
the bucket once this method commits us to taking them.
|
||||
|
||||
#### func (*Bucket) TakeAvailable
|
||||
|
||||
```go
|
||||
func (tb *Bucket) TakeAvailable(count int64) int64
|
||||
```
|
||||
TakeAvailable takes up to count immediately available tokens from the bucket. It
|
||||
returns the number of tokens removed, or zero if there are no available tokens.
|
||||
It does not block.
|
||||
|
||||
#### func (*Bucket) TakeMaxDuration
|
||||
|
||||
```go
|
||||
func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool)
|
||||
```
|
||||
TakeMaxDuration is like Take, except that it will only take tokens from the
|
||||
bucket if the wait time for the tokens is no greater than maxWait.
|
||||
|
||||
If it would take longer than maxWait for the tokens to become available, it does
|
||||
nothing and reports false, otherwise it returns the time that the caller should
|
||||
wait until the tokens are actually available, and reports true.
|
||||
|
||||
#### func (*Bucket) Wait
|
||||
|
||||
```go
|
||||
func (tb *Bucket) Wait(count int64)
|
||||
```
|
||||
Wait takes count tokens from the bucket, waiting until they are available.
|
||||
|
||||
#### func (*Bucket) WaitMaxDuration
|
||||
|
||||
```go
|
||||
func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool
|
||||
```
|
||||
WaitMaxDuration is like Wait except that it will only take tokens from the
|
||||
bucket if it needs to wait for no greater than maxWait. It reports whether any
|
||||
tokens have been removed from the bucket If no tokens have been removed, it
|
||||
returns immediately.
|
|
@ -1,245 +0,0 @@
|
|||
// Copyright 2014 Canonical Ltd.
|
||||
// Licensed under the LGPLv3 with static-linking exception.
|
||||
// See LICENCE file for details.
|
||||
|
||||
// The ratelimit package provides an efficient token bucket implementation
|
||||
// that can be used to limit the rate of arbitrary things.
|
||||
// See http://en.wikipedia.org/wiki/Token_bucket.
|
||||
package ratelimit
|
||||
|
||||
import (
|
||||
"math"
|
||||
"strconv"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// Bucket represents a token bucket that fills at a predetermined rate.
|
||||
// Methods on Bucket may be called concurrently.
|
||||
type Bucket struct {
|
||||
startTime time.Time
|
||||
capacity int64
|
||||
quantum int64
|
||||
fillInterval time.Duration
|
||||
|
||||
// The mutex guards the fields following it.
|
||||
mu sync.Mutex
|
||||
|
||||
// avail holds the number of available tokens
|
||||
// in the bucket, as of availTick ticks from startTime.
|
||||
// It will be negative when there are consumers
|
||||
// waiting for tokens.
|
||||
avail int64
|
||||
availTick int64
|
||||
}
|
||||
|
||||
// NewBucket returns a new token bucket that fills at the
|
||||
// rate of one token every fillInterval, up to the given
|
||||
// maximum capacity. Both arguments must be
|
||||
// positive. The bucket is initially full.
|
||||
func NewBucket(fillInterval time.Duration, capacity int64) *Bucket {
|
||||
return NewBucketWithQuantum(fillInterval, capacity, 1)
|
||||
}
|
||||
|
||||
// rateMargin specifes the allowed variance of actual
|
||||
// rate from specified rate. 1% seems reasonable.
|
||||
const rateMargin = 0.01
|
||||
|
||||
// NewBucketWithRate returns a token bucket that fills the bucket
|
||||
// at the rate of rate tokens per second up to the given
|
||||
// maximum capacity. Because of limited clock resolution,
|
||||
// at high rates, the actual rate may be up to 1% different from the
|
||||
// specified rate.
|
||||
func NewBucketWithRate(rate float64, capacity int64) *Bucket {
|
||||
for quantum := int64(1); quantum < 1<<50; quantum = nextQuantum(quantum) {
|
||||
fillInterval := time.Duration(1e9 * float64(quantum) / rate)
|
||||
if fillInterval <= 0 {
|
||||
continue
|
||||
}
|
||||
tb := NewBucketWithQuantum(fillInterval, capacity, quantum)
|
||||
if diff := math.Abs(tb.Rate() - rate); diff/rate <= rateMargin {
|
||||
return tb
|
||||
}
|
||||
}
|
||||
panic("cannot find suitable quantum for " + strconv.FormatFloat(rate, 'g', -1, 64))
|
||||
}
|
||||
|
||||
// nextQuantum returns the next quantum to try after q.
|
||||
// We grow the quantum exponentially, but slowly, so we
|
||||
// get a good fit in the lower numbers.
|
||||
func nextQuantum(q int64) int64 {
|
||||
q1 := q * 11 / 10
|
||||
if q1 == q {
|
||||
q1++
|
||||
}
|
||||
return q1
|
||||
}
|
||||
|
||||
// NewBucketWithQuantum is similar to NewBucket, but allows
|
||||
// the specification of the quantum size - quantum tokens
|
||||
// are added every fillInterval.
|
||||
func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket {
|
||||
if fillInterval <= 0 {
|
||||
panic("token bucket fill interval is not > 0")
|
||||
}
|
||||
if capacity <= 0 {
|
||||
panic("token bucket capacity is not > 0")
|
||||
}
|
||||
if quantum <= 0 {
|
||||
panic("token bucket quantum is not > 0")
|
||||
}
|
||||
return &Bucket{
|
||||
startTime: time.Now(),
|
||||
capacity: capacity,
|
||||
quantum: quantum,
|
||||
avail: capacity,
|
||||
fillInterval: fillInterval,
|
||||
}
|
||||
}
|
||||
|
||||
// Wait takes count tokens from the bucket, waiting until they are
|
||||
// available.
|
||||
func (tb *Bucket) Wait(count int64) {
|
||||
if d := tb.Take(count); d > 0 {
|
||||
time.Sleep(d)
|
||||
}
|
||||
}
|
||||
|
||||
// WaitMaxDuration is like Wait except that it will
|
||||
// only take tokens from the bucket if it needs to wait
|
||||
// for no greater than maxWait. It reports whether
|
||||
// any tokens have been removed from the bucket
|
||||
// If no tokens have been removed, it returns immediately.
|
||||
func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool {
|
||||
d, ok := tb.TakeMaxDuration(count, maxWait)
|
||||
if d > 0 {
|
||||
time.Sleep(d)
|
||||
}
|
||||
return ok
|
||||
}
|
||||
|
||||
const infinityDuration time.Duration = 0x7fffffffffffffff
|
||||
|
||||
// Take takes count tokens from the bucket without blocking. It returns
|
||||
// the time that the caller should wait until the tokens are actually
|
||||
// available.
|
||||
//
|
||||
// Note that if the request is irrevocable - there is no way to return
|
||||
// tokens to the bucket once this method commits us to taking them.
|
||||
func (tb *Bucket) Take(count int64) time.Duration {
|
||||
d, _ := tb.take(time.Now(), count, infinityDuration)
|
||||
return d
|
||||
}
|
||||
|
||||
// TakeMaxDuration is like Take, except that
|
||||
// it will only take tokens from the bucket if the wait
|
||||
// time for the tokens is no greater than maxWait.
|
||||
//
|
||||
// If it would take longer than maxWait for the tokens
|
||||
// to become available, it does nothing and reports false,
|
||||
// otherwise it returns the time that the caller should
|
||||
// wait until the tokens are actually available, and reports
|
||||
// true.
|
||||
func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool) {
|
||||
return tb.take(time.Now(), count, maxWait)
|
||||
}
|
||||
|
||||
// TakeAvailable takes up to count immediately available tokens from the
|
||||
// bucket. It returns the number of tokens removed, or zero if there are
|
||||
// no available tokens. It does not block.
|
||||
func (tb *Bucket) TakeAvailable(count int64) int64 {
|
||||
return tb.takeAvailable(time.Now(), count)
|
||||
}
|
||||
|
||||
// takeAvailable is the internal version of TakeAvailable - it takes the
|
||||
// current time as an argument to enable easy testing.
|
||||
func (tb *Bucket) takeAvailable(now time.Time, count int64) int64 {
|
||||
if count <= 0 {
|
||||
return 0
|
||||
}
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
|
||||
tb.adjust(now)
|
||||
if tb.avail <= 0 {
|
||||
return 0
|
||||
}
|
||||
if count > tb.avail {
|
||||
count = tb.avail
|
||||
}
|
||||
tb.avail -= count
|
||||
return count
|
||||
}
|
||||
|
||||
// Available returns the number of available tokens. It will be negative
|
||||
// when there are consumers waiting for tokens. Note that if this
|
||||
// returns greater than zero, it does not guarantee that calls that take
|
||||
// tokens from the buffer will succeed, as the number of available
|
||||
// tokens could have changed in the meantime. This method is intended
|
||||
// primarily for metrics reporting and debugging.
|
||||
func (tb *Bucket) Available() int64 {
|
||||
return tb.available(time.Now())
|
||||
}
|
||||
|
||||
// available is the internal version of available - it takes the current time as
|
||||
// an argument to enable easy testing.
|
||||
func (tb *Bucket) available(now time.Time) int64 {
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
tb.adjust(now)
|
||||
return tb.avail
|
||||
}
|
||||
|
||||
// Capacity returns the capacity that the bucket was created with.
|
||||
func (tb *Bucket) Capacity() int64 {
|
||||
return tb.capacity
|
||||
}
|
||||
|
||||
// Rate returns the fill rate of the bucket, in tokens per second.
|
||||
func (tb *Bucket) Rate() float64 {
|
||||
return 1e9 * float64(tb.quantum) / float64(tb.fillInterval)
|
||||
}
|
||||
|
||||
// take is the internal version of Take - it takes the current time as
|
||||
// an argument to enable easy testing.
|
||||
func (tb *Bucket) take(now time.Time, count int64, maxWait time.Duration) (time.Duration, bool) {
|
||||
if count <= 0 {
|
||||
return 0, true
|
||||
}
|
||||
tb.mu.Lock()
|
||||
defer tb.mu.Unlock()
|
||||
|
||||
currentTick := tb.adjust(now)
|
||||
avail := tb.avail - count
|
||||
if avail >= 0 {
|
||||
tb.avail = avail
|
||||
return 0, true
|
||||
}
|
||||
// Round up the missing tokens to the nearest multiple
|
||||
// of quantum - the tokens won't be available until
|
||||
// that tick.
|
||||
endTick := currentTick + (-avail+tb.quantum-1)/tb.quantum
|
||||
endTime := tb.startTime.Add(time.Duration(endTick) * tb.fillInterval)
|
||||
waitTime := endTime.Sub(now)
|
||||
if waitTime > maxWait {
|
||||
return 0, false
|
||||
}
|
||||
tb.avail = avail
|
||||
return waitTime, true
|
||||
}
|
||||
|
||||
// adjust adjusts the current bucket capacity based on the current time.
|
||||
// It returns the current tick.
|
||||
func (tb *Bucket) adjust(now time.Time) (currentTick int64) {
|
||||
currentTick = int64(now.Sub(tb.startTime) / tb.fillInterval)
|
||||
|
||||
if tb.avail >= tb.capacity {
|
||||
return
|
||||
}
|
||||
tb.avail += (currentTick - tb.availTick) * tb.quantum
|
||||
if tb.avail > tb.capacity {
|
||||
tb.avail = tb.capacity
|
||||
}
|
||||
tb.availTick = currentTick
|
||||
return
|
||||
}
|
|
@ -1,51 +0,0 @@
|
|||
// Copyright 2014 Canonical Ltd.
|
||||
// Licensed under the LGPLv3 with static-linking exception.
|
||||
// See LICENCE file for details.
|
||||
|
||||
package ratelimit
|
||||
|
||||
import "io"
|
||||
|
||||
type reader struct {
|
||||
r io.Reader
|
||||
bucket *Bucket
|
||||
}
|
||||
|
||||
// Reader returns a reader that is rate limited by
|
||||
// the given token bucket. Each token in the bucket
|
||||
// represents one byte.
|
||||
func Reader(r io.Reader, bucket *Bucket) io.Reader {
|
||||
return &reader{
|
||||
r: r,
|
||||
bucket: bucket,
|
||||
}
|
||||
}
|
||||
|
||||
func (r *reader) Read(buf []byte) (int, error) {
|
||||
n, err := r.r.Read(buf)
|
||||
if n <= 0 {
|
||||
return n, err
|
||||
}
|
||||
r.bucket.Wait(int64(n))
|
||||
return n, err
|
||||
}
|
||||
|
||||
type writer struct {
|
||||
w io.Writer
|
||||
bucket *Bucket
|
||||
}
|
||||
|
||||
// Writer returns a reader that is rate limited by
|
||||
// the given token bucket. Each token in the bucket
|
||||
// represents one byte.
|
||||
func Writer(w io.Writer, bucket *Bucket) io.Writer {
|
||||
return &writer{
|
||||
w: w,
|
||||
bucket: bucket,
|
||||
}
|
||||
}
|
||||
|
||||
func (w *writer) Write(buf []byte) (int, error) {
|
||||
w.bucket.Wait(int64(len(buf)))
|
||||
return w.w.Write(buf)
|
||||
}
|
Loading…
Reference in New Issue