445f20dbdb
Before deleting an object based on absent owners, GC verifies absence of those owners with a live lookup. The coordinates used to perform that live lookup are the ones specified in the ownerReference of the child. In order to performantly delete multiple children from the same parent (e.g. 1000 pods from a replicaset), a 404 response to a lookup is cached in absentOwnerCache. Previously, the cache was a simple uid set. However, since children can disagree on the coordinates that should be used to look up a given uid, the cache should record the exact coordinates verified absent. This is a [apiVersion, kind, namespace, name, uid] tuple.
52 lines
1.3 KiB
Go
52 lines
1.3 KiB
Go
/*
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Copyright 2016 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package garbagecollector
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import (
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"sync"
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"github.com/golang/groupcache/lru"
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)
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// ReferenceCache is an LRU cache for uid.
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type ReferenceCache struct {
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mutex sync.Mutex
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cache *lru.Cache
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}
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// NewReferenceCache returns a ReferenceCache.
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func NewReferenceCache(maxCacheEntries int) *ReferenceCache {
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return &ReferenceCache{
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cache: lru.New(maxCacheEntries),
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}
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}
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// Add adds a uid to the cache.
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func (c *ReferenceCache) Add(reference objectReference) {
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c.mutex.Lock()
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defer c.mutex.Unlock()
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c.cache.Add(reference, nil)
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}
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// Has returns if a uid is in the cache.
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func (c *ReferenceCache) Has(reference objectReference) bool {
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c.mutex.Lock()
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defer c.mutex.Unlock()
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_, found := c.cache.Get(reference)
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return found
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}
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