Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

runtime: fix MemStats.{PauseNS,PauseEnd,PauseTotalNS,LastGC}

Browse source 
These memstats are currently being computed by gcMark, which was
appropriate in Go 1.4, but gcMark is now just one part of a bigger
picture. In particular, it can't account for the sweep termination
pause time, it can't account for all of the mark termination pause
time, and the reported "pause end" and "last GC" times will be
slightly earlier than they really are.

Lift computing of these statistics into func gc, which has the
appropriate visibility into the process to compute them correctly.

Fixes one of the issues in #10323. This does not add new statistics
appropriate to the concurrent collector; it simply fixes existing
statistics that are being misreported.

Change-Id: I670cb16594a8641f6b27acf4472db15b6e8e086e
Reviewed-on: https://go-review.googlesource.com/11794
Reviewed-by: Russ Cox <rsc@golang.org>
This commit is contained in:
Austin Clements 2015-07-01 11:04:19 -04:00
parent ad60cd8b92
commit 777ab5ce1a
2 changed files with 42 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

17
src/runtime/malloc_test.go
View file

@ -32,7 +32,7 @@ func TestMemStats(t *testing.T) {
st.HeapIdle > 1e10 || st.HeapInuse > 1e10 || st.HeapObjects > 1e10 || st.StackInuse > 1e10 ||
st.StackSys > 1e10 || st.MSpanInuse > 1e10 || st.MSpanSys > 1e10 || st.MCacheInuse > 1e10 ||
st.MCacheSys > 1e10 || st.BuckHashSys > 1e10 || st.GCSys > 1e10 || st.OtherSys > 1e10 ||
st.NextGC > 1e10 || st.NumGC > 1e9 {
st.NextGC > 1e10 || st.NumGC > 1e9 || st.PauseTotalNs > 1e11 {
t.Fatalf("Insanely high value (overflow?): %+v", *st)
}
@ -48,6 +48,21 @@ func TestMemStats(t *testing.T) {
if lpe := st.PauseEnd[int(st.NumGC+255)%len(st.PauseEnd)]; st.LastGC != lpe {
t.Fatalf("LastGC(%d) != last PauseEnd(%d)", st.LastGC, lpe)
}
var pauseTotal uint64
for _, pause := range st.PauseNs {
pauseTotal += pause
}
if int(st.NumGC) < len(st.PauseNs) {
// We have all pauses, so this should be exact.
if st.PauseTotalNs != pauseTotal {
t.Fatalf("PauseTotalNs(%d) != sum PauseNs(%d)", st.PauseTotalNs, pauseTotal)
}
} else {
if st.PauseTotalNs < pauseTotal {
t.Fatalf("PauseTotalNs(%d) < sum PauseNs(%d)", st.PauseTotalNs, pauseTotal)
}
}
}
func TestStringConcatenationAllocs(t *testing.T) {