mirror of
https://github.com/gogrlx/nats-server.git
synced 2026-04-02 03:38:42 -07:00
2baac47820
* No functional changes * Did not address the ALL_CAPS issues * Did not modify public APIs and field names.
44 lines
895 B
Go
44 lines
895 B
Go
// Copyright 2012-2013 Apcera Inc. All rights reserved.
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package hashmap
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import (
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"math/rand"
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"time"
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)
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// We use init to setup the random number generator
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func init() {
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rand.Seed(time.Now().UnixNano())
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}
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// RemoveRandom can be used for a random policy eviction.
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// This is stochastic but very fast and does not impede
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// performance like LRU, LFU or even ARC based implementations.
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func (h *HashMap) RemoveRandom() {
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if h.used == 0 {
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return
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}
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index := (rand.Int()) & int(h.msk)
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// Walk forward til we find an entry
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for i := index; i < len(h.bkts); i++ {
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e := &h.bkts[i]
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if *e != nil {
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*e = (*e).next
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h.used--
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return
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}
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}
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// If we are here we hit end and did not remove anything,
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// use the index and walk backwards.
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for i := index; i >= 0; i-- {
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e := &h.bkts[i]
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if *e != nil {
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*e = (*e).next
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h.used--
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return
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}
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}
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panic("Should not reach here..")
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}
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