// loop over an array/a slicefor i, e :=range a {// i is the index, e the element}// if you only need e:for _, e :=range a {// e is the element}// ...and if you only need the indexfor i :=range a {}// In Go pre-1.4, you'll get a compiler error if you'...
since t.hasher may panic,// in which case we have not actually done a write. h.flags ^= hashWritingif h.buckets == nil { h.buckets = newobject(t.bucket) // newarray(t.bucket, 1) }again:// 省略 ...bucketloop:// 省略 ....
➜ test go test --bench='Loop' -run=none -benchmem goos: darwin goarch: amd64 pkg: gotest666/test cpu: Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz BenchmarkLoopFor-12 4334842 270.8 ns/op 0 B/op 0 allocs/op BenchmarkLoopRangeIndex-12 4436786 272.7 ns/op 0 B/op 0 allocs/o...
在bucketloop循环中,哈希会依次遍历正常桶和溢出桶中的数据,它会比较这 8 位数字和桶中存储的tophash,每一个桶都存储键对应的tophash,每一次读写操作都会与桶中所有的tophash进行比较,用于选择桶序号的是哈希的最低几位,而用于加速访问的是哈希的高 8 位,这种设计能够减少同一个桶中有大量相等tophash的概率。
id } _ = tmp } } func BenchmarkLoopRangeValue(b *testing.B) { var items [1024]Item for i := 0; i < b.N; i++ { var tmp int for _, item := range items { tmp = item.id } _ = tmp } } 代码语言:javascript 代码运行次数:0 运行 AI代码解释 ➜ test go test --bench=...
}// 预先分配固定 Size 的池子p.workers=newWorkerArray(loopQueueType,size)}else{// 初始化不创建,运行时再创建p.workers=newWorkerArray(stackType,0)} p.cond=sync.NewCond(p.lock)// 开启一个goroutine清理过期的 workergo p.purgePeriodically()returnp,nil ...
In the above program,iis initialised to1. The conditional statement will check whetheri <= 10. If the condition istrue, the value ofiis printed, else the loop is terminated. The post statement incrementsiby1at the end of each iteration. Onceiis greater than10, the loop terminates. ...
{ // The P got a new worker. // Exit this worker. return false } } return true }, unsafe.Pointer(park), "GC worker (idle)", traceEvGoBlock, 0) // 检查P的gcBgMarkWorker是否和当前的G一致, 不一致时结束当前的任务 // Loop until the P dies and disassociates this // worker (the...
h.buckets = newobject(t.bucket)// newarray(t.bucket, 1) } again: // 省略 ... bucketloop: // 省略 ... done: ifh.flags&hashWriting ==0{ fatal("concurrent map writes") } h.flags &^= hashWriting ift.indirectelem { elem = *((*unsafe.Pointer)(elem)) ...
=top{// 优化寻址,tophash数组复用了标志位,一旦检测到emptyRest则跳出外层大循环,返回key在map中未找到ifb.tophash[i]==emptyRest{breakbucketloop}// key的tophash和tophash数组中的某个元素不相等,则进入小循环的下一个index的对比,或者进入大循环的下一个桶链表的查找continue}// 走到这一步,就是tophash...