platform_build_soong/ui/metrics/time.go
Patrice Arruda 958b89c0b5 Use monotonic clock instead of wall time clock for metrics.
From several dashboards, there are high spikes from several
builds where the real time of executing a part of the build
system took many many hours. This is due to using the wall
time clock when calculating the duration. For metrics, the
monotonic clock should be used for more accurate measurement.
Also, cleaned up the time.go file to use the proper proto
functions when marshalling perf protobuf and deleted
unnecessary functions.

Bug: b/143492984
Test: Wrote and ran unit test case.
Change-Id: I1540cfbf37915e3045ecedaa2595c1f9429bcd62
2020-07-13 21:14:34 +00:00

69 lines
1.9 KiB
Go

// Copyright 2018 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package metrics
import (
"time"
"android/soong/ui/metrics/metrics_proto"
"android/soong/ui/tracer"
"github.com/golang/protobuf/proto"
)
// for testing purpose only
var _now = now
type timeEvent struct {
desc string
name string
// the time that the event started to occur.
start time.Time
}
type TimeTracer interface {
Begin(name, desc string, thread tracer.Thread)
End(thread tracer.Thread) soong_metrics_proto.PerfInfo
}
type timeTracerImpl struct {
activeEvents []timeEvent
}
var _ TimeTracer = &timeTracerImpl{}
func now() time.Time {
return time.Now()
}
func (t *timeTracerImpl) Begin(name, desc string, _ tracer.Thread) {
t.activeEvents = append(t.activeEvents, timeEvent{name: name, desc: desc, start: _now()})
}
func (t *timeTracerImpl) End(tracer.Thread) soong_metrics_proto.PerfInfo {
if len(t.activeEvents) < 1 {
panic("Internal error: No pending events for endAt to end!")
}
lastEvent := t.activeEvents[len(t.activeEvents)-1]
t.activeEvents = t.activeEvents[:len(t.activeEvents)-1]
realTime := uint64(_now().Sub(lastEvent.start).Nanoseconds())
return soong_metrics_proto.PerfInfo{
Desc: proto.String(lastEvent.desc),
Name: proto.String(lastEvent.name),
StartTime: proto.Uint64(uint64(lastEvent.start.UnixNano())),
RealTime: proto.Uint64(realTime),
}
}