diff options
| author | Austin Clements <austin@google.com> | 2017-04-18 16:41:19 -0400 |
|---|---|---|
| committer | Austin Clements <austin@google.com> | 2017-04-20 19:35:08 +0000 |
| commit | 0c0c94a9dcf90fbb48343d5a02787758d64e306d (patch) | |
| tree | c4cdaa8365646caa9abe95876dcc07fbb587c784 /src/runtime/pprof | |
| parent | f3f3f0d6d509bfaf30b55c0679cff366b50b7eae (diff) | |
| download | go-0c0c94a9dcf90fbb48343d5a02787758d64e306d.tar.xz | |
runtime/pprof: fix period information
The period recorded in CPU profiles is in nanoseconds, but was being
computed incorrectly as hz * 1000. As a result, many absolute times
displayed by pprof were incorrect.
Fix this by computing the period correctly.
Change-Id: I6fadd6d8ad3e57f31e8cc7a25a24fcaec510d8d4
Reviewed-on: https://go-review.googlesource.com/40995
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Diffstat (limited to 'src/runtime/pprof')
| -rw-r--r-- | src/runtime/pprof/proto.go | 4 | ||||
| -rw-r--r-- | src/runtime/pprof/proto_test.go | 4 |
2 files changed, 5 insertions, 3 deletions
diff --git a/src/runtime/pprof/proto.go b/src/runtime/pprof/proto.go index 0f74e119b6..923fa2188a 100644 --- a/src/runtime/pprof/proto.go +++ b/src/runtime/pprof/proto.go @@ -270,7 +270,9 @@ func (b *profileBuilder) addCPUData(data []uint64, tags []unsafe.Pointer) error if data[0] != 3 || data[2] == 0 { return fmt.Errorf("malformed profile") } - b.period = int64(data[2]) * 1000 + // data[2] is sampling rate in Hz. Convert to sampling + // period in nanoseconds. + b.period = 1e9 / int64(data[2]) b.havePeriod = true data = data[3:] } diff --git a/src/runtime/pprof/proto_test.go b/src/runtime/pprof/proto_test.go index 2f10419147..59c1080e7b 100644 --- a/src/runtime/pprof/proto_test.go +++ b/src/runtime/pprof/proto_test.go @@ -40,7 +40,7 @@ func TestConvertCPUProfileEmpty(t *testing.T) { // A test server with mock cpu profile data. var buf bytes.Buffer - b := []uint64{3, 0, 2000} // empty profile with 2ms sample period + b := []uint64{3, 0, 500} // empty profile at 500 Hz (2ms sample period) p, err := translateCPUProfile(b) if err != nil { t.Fatalf("translateCPUProfile: %v", err) @@ -103,7 +103,7 @@ func TestConvertCPUProfile(t *testing.T) { addr1, addr2, map1, map2 := testPCs(t) b := []uint64{ - 3, 0, 2000, // periodMs = 2000 + 3, 0, 500, // hz = 500 5, 0, 10, uint64(addr1), uint64(addr1 + 2), // 10 samples in addr1 5, 0, 40, uint64(addr2), uint64(addr2 + 2), // 40 samples in addr2 5, 0, 10, uint64(addr1), uint64(addr1 + 2), // 10 samples in addr1 |