From d0ebeefbc40e30a96ec9b788353ff6969719fdd9 Mon Sep 17 00:00:00 2001
From: "Bobby (Babak) Salamat" <bsalamat@google.com>
Date: Mon, 11 Feb 2019 13:37:30 -0800
Subject: [PATCH] Use runtime.NumCPU() instead of a fixed value for parallel
 scheduler threads.

---
 pkg/scheduler/algorithm/predicates/metadata.go          | 5 +++--
 pkg/scheduler/algorithm/priorities/interpod_affinity.go | 3 ++-
 pkg/scheduler/core/generic_scheduler.go                 | 7 ++++---
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/pkg/scheduler/algorithm/predicates/metadata.go b/pkg/scheduler/algorithm/predicates/metadata.go
index 99baed71ab..8e27d4f721 100644
--- a/pkg/scheduler/algorithm/predicates/metadata.go
+++ b/pkg/scheduler/algorithm/predicates/metadata.go
@@ -19,6 +19,7 @@ package predicates
 import (
 	"context"
 	"fmt"
+	"runtime"
 	"sync"
 
 	"k8s.io/klog"
@@ -415,7 +416,7 @@ func getTPMapMatchingExistingAntiAffinity(pod *v1.Pod, nodeInfoMap map[string]*s
 			appendTopologyPairsMaps(existingPodTopologyMaps)
 		}
 	}
-	workqueue.ParallelizeUntil(context.TODO(), 16, len(allNodeNames), processNode)
+	workqueue.ParallelizeUntil(context.TODO(), runtime.NumCPU(), len(allNodeNames), processNode)
 	return topologyMaps, firstError
 }
 
@@ -503,7 +504,7 @@ func getTPMapMatchingIncomingAffinityAntiAffinity(pod *v1.Pod, nodeInfoMap map[s
 			appendResult(node.Name, nodeTopologyPairsAffinityPodsMaps, nodeTopologyPairsAntiAffinityPodsMaps)
 		}
 	}
-	workqueue.ParallelizeUntil(context.TODO(), 16, len(allNodeNames), processNode)
+	workqueue.ParallelizeUntil(context.TODO(), runtime.NumCPU(), len(allNodeNames), processNode)
 	return topologyPairsAffinityPodsMaps, topologyPairsAntiAffinityPodsMaps, firstError
 }
 
diff --git a/pkg/scheduler/algorithm/priorities/interpod_affinity.go b/pkg/scheduler/algorithm/priorities/interpod_affinity.go
index 62540a5941..24af001ffa 100644
--- a/pkg/scheduler/algorithm/priorities/interpod_affinity.go
+++ b/pkg/scheduler/algorithm/priorities/interpod_affinity.go
@@ -18,6 +18,7 @@ package priorities
 
 import (
 	"context"
+	"runtime"
 	"sync"
 
 	"k8s.io/api/core/v1"
@@ -211,7 +212,7 @@ func (ipa *InterPodAffinity) CalculateInterPodAffinityPriority(pod *v1.Pod, node
 			}
 		}
 	}
-	workqueue.ParallelizeUntil(context.TODO(), 16, len(allNodeNames), processNode)
+	workqueue.ParallelizeUntil(context.TODO(), runtime.NumCPU(), len(allNodeNames), processNode)
 	if pm.firstError != nil {
 		return nil, pm.firstError
 	}
diff --git a/pkg/scheduler/core/generic_scheduler.go b/pkg/scheduler/core/generic_scheduler.go
index 59a4d40179..e726060214 100644
--- a/pkg/scheduler/core/generic_scheduler.go
+++ b/pkg/scheduler/core/generic_scheduler.go
@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"math"
+	"runtime"
 	"sort"
 	"strings"
 	"sync"
@@ -487,7 +488,7 @@ func (g *genericScheduler) findNodesThatFit(pod *v1.Pod, nodes []*v1.Node) ([]*v
 
 		// Stops searching for more nodes once the configured number of feasible nodes
 		// are found.
-		workqueue.ParallelizeUntil(ctx, 16, int(allNodes), checkNode)
+		workqueue.ParallelizeUntil(ctx, runtime.NumCPU(), int(allNodes), checkNode)
 
 		filtered = filtered[:filteredLen]
 		if len(errs) > 0 {
@@ -693,7 +694,7 @@ func PrioritizeNodes(
 		}
 	}
 
-	workqueue.ParallelizeUntil(context.TODO(), 16, len(nodes), func(index int) {
+	workqueue.ParallelizeUntil(context.TODO(), runtime.NumCPU(), len(nodes), func(index int) {
 		nodeInfo := nodeNameToInfo[nodes[index].Name]
 		for i := range priorityConfigs {
 			if priorityConfigs[i].Function != nil {
@@ -941,7 +942,7 @@ func selectNodesForPreemption(pod *v1.Pod,
 			resultLock.Unlock()
 		}
 	}
-	workqueue.ParallelizeUntil(context.TODO(), 16, len(potentialNodes), checkNode)
+	workqueue.ParallelizeUntil(context.TODO(), runtime.NumCPU(), len(potentialNodes), checkNode)
 	return nodeToVictims, nil
 }