62 lines
1.2 KiB
Go
62 lines
1.2 KiB
Go
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package sync
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import (
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"log"
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"math/rand"
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"sync"
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"sync/atomic"
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"testing"
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"time"
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)
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const (
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//模拟的最大goroutine
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maxGoroutine = 5
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)
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func TestPool(t *testing.T) {
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//等待任务完成
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var wg sync.WaitGroup
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wg.Add(maxGoroutine)
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p := &sync.Pool{
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New: createConnection,
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}
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//模拟好几个goroutine同时使用资源池查询数据
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for query := 0; query < maxGoroutine; query++ {
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go func(q int) {
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dbQuery(q, p)
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wg.Done()
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}(query)
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}
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wg.Wait()
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}
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//模拟数据库查询
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func dbQuery(query int, pool *sync.Pool) {
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conn := pool.Get().(*dbConnection)
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defer pool.Put(conn)
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//模拟查询
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time.Sleep(time.Duration(rand.Intn(1000)) * time.Millisecond)
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log.Printf("第%d个查询，使用的是ID为%d的数据库连接", query, conn.ID)
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}
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//数据库连接
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type dbConnection struct {
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ID int32 //连接的标志
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}
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//实现io.Closer接口
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func (db *dbConnection) Close() error {
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log.Println("关闭连接", db.ID)
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return nil
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}
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var idCounter int32
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//生成数据库连接的方法，以供资源池使用
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func createConnection() interface{} {
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//并发安全，给数据库连接生成唯一标志
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id := atomic.AddInt32(&idCounter, 1)
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return &dbConnection{ID: id}
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}
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