mirror of https://github.com/k3s-io/k3s
70 lines
1.9 KiB
Go
70 lines
1.9 KiB
Go
// Copyright 2016 The etcd 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 contention
|
|
|
|
import (
|
|
"sync"
|
|
"time"
|
|
)
|
|
|
|
// TimeoutDetector detects routine starvations by
|
|
// observing the actual time duration to finish an action
|
|
// or between two events that should happen in a fixed
|
|
// interval. If the observed duration is longer than
|
|
// the expectation, the detector will report the result.
|
|
type TimeoutDetector struct {
|
|
mu sync.Mutex // protects all
|
|
maxDuration time.Duration
|
|
// map from event to time
|
|
// time is the last seen time of the event.
|
|
records map[uint64]time.Time
|
|
}
|
|
|
|
// NewTimeoutDetector creates the TimeoutDetector.
|
|
func NewTimeoutDetector(maxDuration time.Duration) *TimeoutDetector {
|
|
return &TimeoutDetector{
|
|
maxDuration: maxDuration,
|
|
records: make(map[uint64]time.Time),
|
|
}
|
|
}
|
|
|
|
// Reset resets the NewTimeoutDetector.
|
|
func (td *TimeoutDetector) Reset() {
|
|
td.mu.Lock()
|
|
defer td.mu.Unlock()
|
|
|
|
td.records = make(map[uint64]time.Time)
|
|
}
|
|
|
|
// Observe observes an event for given id. It returns false and exceeded duration
|
|
// if the interval is longer than the expectation.
|
|
func (td *TimeoutDetector) Observe(which uint64) (bool, time.Duration) {
|
|
td.mu.Lock()
|
|
defer td.mu.Unlock()
|
|
|
|
ok := true
|
|
now := time.Now()
|
|
exceed := time.Duration(0)
|
|
|
|
if pt, found := td.records[which]; found {
|
|
exceed = now.Sub(pt) - td.maxDuration
|
|
if exceed > 0 {
|
|
ok = false
|
|
}
|
|
}
|
|
td.records[which] = now
|
|
return ok, exceed
|
|
}
|