62 lines
1.5 KiB
Go
62 lines
1.5 KiB
Go
// Copyright 2019, OpenCensus Authors
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//
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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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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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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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package trace
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import (
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"github.com/golang/groupcache/lru"
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)
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// A simple lru.Cache wrapper that tracks the keys of the current contents and
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// the cumulative number of evicted items.
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type lruMap struct {
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cacheKeys map[lru.Key]bool
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cache *lru.Cache
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droppedCount int
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}
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func newLruMap(size int) *lruMap {
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lm := &lruMap{
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cacheKeys: make(map[lru.Key]bool),
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cache: lru.New(size),
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droppedCount: 0,
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}
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lm.cache.OnEvicted = func(key lru.Key, value interface{}) {
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delete(lm.cacheKeys, key)
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lm.droppedCount++
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}
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return lm
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}
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func (lm lruMap) len() int {
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return lm.cache.Len()
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}
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func (lm lruMap) keys() []interface{} {
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keys := make([]interface{}, len(lm.cacheKeys))
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for k := range lm.cacheKeys {
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keys = append(keys, k)
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}
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return keys
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}
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func (lm *lruMap) add(key, value interface{}) {
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lm.cacheKeys[lru.Key(key)] = true
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lm.cache.Add(lru.Key(key), value)
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}
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func (lm *lruMap) get(key interface{}) (interface{}, bool) {
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return lm.cache.Get(key)
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}
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