fix RT may be 0 (#26)

* fix RT may be 0


Co-authored-by: chenzhihui <chenzhihui@bilibili.com>

Makefile

@@ -5,7 +5,7 @@ PKG_DIR?=''
 
 LINTER := bin/golangci-lint
 $(LINTER): 
- curl -L https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | sh -s v1.42.0
+ curl -SL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s latest
 
 .PHONY: test
 test:
@@ -21,4 +21,4 @@ lint: $(LINTER)
 
 .PHONY: build
 build:
- ${TOOLS_SH} build ${PKG_DIR} 
+ ${TOOLS_SH} build ${PKG_DIR} 

ratelimit/bbr/bbr.go

@@ -43,12 +43,20 @@ func cpuproc() {
  for range ticker.C {
  stat := &cpu.Stat{}
  cpu.ReadStat(stat)
+ stat.Usage = min(stat.Usage, 1000)
  prevCPU := atomic.LoadInt64(&gCPU)
  curCPU := int64(float64(prevCPU)*decay + float64(stat.Usage)*(1.0-decay))
  atomic.StoreInt64(&gCPU, curCPU)
  }
 }
 
+func min(l, r uint64) uint64 {
+ if l < r {
+ return l
+ }
+ return r
+}
+
 // Stat contains the metrics snapshot of bbr.
 type Stat struct {
  CPU int64
@@ -288,8 +296,10 @@ func (l *BBR) Allow() (ratelimit.DoneFunc, error) {
  }
  atomic.AddInt64(&l.inFlight, 1)
  start := time.Now().UnixNano()
+ ms := float64(time.Millisecond)
  return func(ratelimit.DoneInfo) {
- rt := (time.Now().UnixNano() - start) / int64(time.Millisecond)
+ //nolint
+ rt := int64(math.Ceil(float64(time.Now().UnixNano()-start)) / ms)
  l.rtStat.Add(rt)
  atomic.AddInt64(&l.inFlight, -1)
  l.passStat.Add(1)