From 028e85aceb30911f7db38cdc494f046a2cda21b2 Mon Sep 17 00:00:00 2001
From: Tony Chen <zhihui_chen@foxmail.com>
Date: Tue, 21 Jun 2022 20:46:45 +0800
Subject: [PATCH] fix RT may be 0 (#26)

* fix RT may be 0


Co-authored-by: chenzhihui <chenzhihui@bilibili.com>
---
 Makefile             |  4 ++--
 ratelimit/bbr/bbr.go | 12 +++++++++++-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index 9d85157..dde667a 100644
--- a/Makefile
+++ b/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}	
\ No newline at end of file
+	${TOOLS_SH} build ${PKG_DIR}	
diff --git a/ratelimit/bbr/bbr.go b/ratelimit/bbr/bbr.go
index d53fb16..20fe9f3 100644
--- a/ratelimit/bbr/bbr.go
+++ b/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)