forked from Shiloh/githaven
59 lines
1.4 KiB
Go
59 lines
1.4 KiB
Go
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// Copyright 2015 PingCAP, Inc.
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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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// See the License for the specific language governing permissions and
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// limitations under the License.
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package kv
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import (
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"sync"
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"github.com/ngaut/log"
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)
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// A cache holds a set of reusable objects.
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// The slice is a stack (LIFO).
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// If more are needed, the cache creates them by calling new.
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type cache struct {
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mu sync.Mutex
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name string
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saved []MemBuffer
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// factory
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fact func() MemBuffer
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}
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func (c *cache) put(x MemBuffer) {
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c.mu.Lock()
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if len(c.saved) < cap(c.saved) {
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c.saved = append(c.saved, x)
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} else {
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log.Warnf("%s is full, size: %d, you may need to increase pool size", c.name, len(c.saved))
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}
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c.mu.Unlock()
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}
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func (c *cache) get() MemBuffer {
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c.mu.Lock()
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n := len(c.saved)
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if n == 0 {
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c.mu.Unlock()
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return c.fact()
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}
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x := c.saved[n-1]
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c.saved = c.saved[0 : n-1]
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c.mu.Unlock()
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return x
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}
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func newCache(name string, cap int, fact func() MemBuffer) *cache {
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return &cache{name: name, saved: make([]MemBuffer, 0, cap), fact: fact}
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}
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