1239 lines
35 KiB
Go
1239 lines
35 KiB
Go
// Copyright 2022 The Tint Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package main
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import (
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"context"
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"crypto/sha256"
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"encoding/hex"
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"encoding/json"
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"errors"
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"flag"
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"fmt"
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"io"
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"log"
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"math"
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"os"
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"os/exec"
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"path/filepath"
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"reflect"
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"regexp"
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"sort"
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"strings"
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"time"
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"dawn.googlesource.com/dawn/tools/src/bench"
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"dawn.googlesource.com/dawn/tools/src/git"
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"github.com/andygrunwald/go-gerrit"
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"github.com/shirou/gopsutil/cpu"
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)
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// main entry point
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func main() {
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var cfgPath string
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flag.StringVar(&cfgPath, "c", "~/.config/perfmon/config.json", "the config file")
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flag.Parse()
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if err := run(cfgPath); err != nil {
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fmt.Fprintln(os.Stderr, err)
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os.Exit(1)
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}
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}
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// run starts the perfmon tool with the given config path
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func run(cfgPath string) error {
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cfgPath, err := expandHomeDir(cfgPath)
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if err != nil {
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return err
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}
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if err := findTools(); err != nil {
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return err
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}
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g, err := git.New(tools.git)
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if err != nil {
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return err
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}
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cfg, err := loadConfig(cfgPath)
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if err != nil {
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return err
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}
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dawnDir, resultsDir, err := makeWorkingDirs(cfg)
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if err != nil {
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return err
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}
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dawnRepo, err := createOrOpenGitRepo(g, dawnDir, cfg.Dawn)
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if err != nil {
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return err
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}
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resultsRepo, err := createOrOpenGitRepo(g, resultsDir, cfg.Results)
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if err != nil {
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return err
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}
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gerritClient, err := gerrit.NewClient(cfg.Gerrit.URL, nil)
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if err != nil {
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return err
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}
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gerritClient.Authentication.SetBasicAuth(cfg.Gerrit.Username, cfg.Gerrit.Password)
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sysInfo, err := cpu.Info()
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if err != nil {
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return fmt.Errorf("failed to obtain system info:\n %v", err)
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}
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// Some machines report slightly different CPU clock speeds each reboot
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// To work around this, quantize the reported speed to the nearest 100MHz
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for i, s := range sysInfo {
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sysInfo[i].Mhz = math.Round(s.Mhz/100) * 100
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}
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e := env{
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cfg: cfg,
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git: g,
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system: sysInfo,
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systemID: hash(sysInfo)[:8],
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dawnDir: dawnDir,
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buildDir: filepath.Join(dawnDir, "out"),
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resultsDir: resultsDir,
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dawnRepo: dawnRepo,
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resultsRepo: resultsRepo,
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gerrit: gerritClient,
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benchmarkCache: map[git.Hash]*bench.Run{},
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}
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for {
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didSomething, err := e.doSomeWork()
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if err != nil {
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log.Printf("ERROR: %v", err)
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log.Printf("Pausing...")
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time.Sleep(time.Minute * 10)
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continue
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}
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if !didSomething {
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log.Println("nothing to do. Sleeping...")
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time.Sleep(time.Minute * 5)
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}
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}
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}
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// Config holds the root configuration options for the perfmon tool
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type Config struct {
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WorkingDir string
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RootChange git.Hash
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Dawn GitConfig
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Results GitConfig
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Gerrit GerritConfig
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Timeouts TimeoutsConfig
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ExternalAccounts []string
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BenchmarkRepetitions int
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BenchmarkMaxTemp float32 // celsius
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CPUTempSensorName string // Name of the sensor to use for CPU temp
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ExternalBenchmarkCorpus string
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}
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// GitConfig holds the configuration options for accessing a git repo
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type GitConfig struct {
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URL string
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Branch string
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Credentials git.Credentials
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}
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// GerritConfig holds the configuration options for accessing gerrit
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type GerritConfig struct {
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URL string
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Username string
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Email string
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Password string
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}
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// TimeoutsConfig holds the configuration options for timeouts
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type TimeoutsConfig struct {
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Sync time.Duration
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Build time.Duration
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Benchmark time.Duration
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}
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// HistoricResults contains the full set of historic benchmark results for a
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// given system
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type HistoricResults struct {
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System []cpu.InfoStat
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Commits []CommitResults
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}
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// CommitResults holds the results of a single dawn commit
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type CommitResults struct {
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Commit string
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CommitTime time.Time
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CommitDescription string
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Benchmarks []Benchmark
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}
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// Benchmark holds the benchmark results for a single test
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type Benchmark struct {
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Name string
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Time float64
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Repeats int `json:",omitempty"`
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}
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// AuthConfig holds the authentication options for accessing a git repo
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type AuthConfig struct {
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Username string
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Password string
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}
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// setDefaults assigns default values to unassigned fields of cfg
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func (cfg *Config) setDefaults() {
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if cfg.RootChange.IsZero() {
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cfg.RootChange, _ = git.ParseHash("e72e42d9e0c851311512ca6da4d7b59f0bcc60d9")
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}
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cfg.Dawn.setDefaults()
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cfg.Results.setDefaults()
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cfg.Timeouts.setDefaults()
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if cfg.BenchmarkRepetitions < 1 {
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cfg.BenchmarkRepetitions = 1
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}
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if cfg.BenchmarkMaxTemp == 0 {
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cfg.BenchmarkMaxTemp = 50
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}
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}
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// setDefaults assigns default values to unassigned fields of cfg
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func (cfg *GitConfig) setDefaults() {
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if cfg.Branch == "" {
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cfg.Branch = "main"
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}
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}
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// setDefaults assigns default values to unassigned fields of cfg
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func (cfg *TimeoutsConfig) setDefaults() {
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if cfg.Sync == 0 {
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cfg.Sync = time.Minute * 30
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}
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if cfg.Build == 0 {
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cfg.Build = time.Minute * 30
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}
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if cfg.Benchmark == 0 {
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cfg.Benchmark = time.Minute * 30
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}
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}
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// findCommitResults looks for a CommitResult with the given commit id,
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// returning a pointer to the CommitResult if found, otherwise nil
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func (h *HistoricResults) findCommitResults(commit string) *CommitResults {
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for i, c := range h.Commits {
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if c.Commit == commit {
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return &h.Commits[i]
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}
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}
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return nil
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}
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// sorts all the benchmarks by commit date
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func (h *HistoricResults) sort() {
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sort.Slice(h.Commits, func(i, j int) bool {
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if h.Commits[i].CommitTime.Before(h.Commits[j].CommitTime) {
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return true
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}
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if h.Commits[j].CommitTime.Before(h.Commits[i].CommitTime) {
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return false
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}
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return h.Commits[i].CommitDescription < h.Commits[j].CommitDescription
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})
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}
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// findBenchmark looks for a Benchmark with the given commit id,
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// returning a pointer to the Benchmark if found, otherwise nil
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func (r *CommitResults) findBenchmark(name string) *Benchmark {
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for i, b := range r.Benchmarks {
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if b.Name == name {
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return &r.Benchmarks[i]
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}
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}
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return nil
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}
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// sorts all the benchmarks by name
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func (r *CommitResults) sort() {
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sort.Slice(r.Benchmarks, func(i, j int) bool {
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return r.Benchmarks[i].Name < r.Benchmarks[j].Name
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})
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}
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// env holds the perfmon main environment state
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type env struct {
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cfg Config
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git *git.Git
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system []cpu.InfoStat
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systemID string
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dawnDir string
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buildDir string
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resultsDir string
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dawnRepo *git.Repository
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resultsRepo *git.Repository
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gerrit *gerrit.Client
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benchmarkCache map[git.Hash]*bench.Run
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}
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// doSomeWork scans gerrit for changes up for review and submitted changes to
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// benchmark. If something was found to do, then returns true.
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func (e env) doSomeWork() (bool, error) {
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{
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log.Println("scanning for review changes to benchmark...")
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change, err := e.findGerritChangeToBenchmark()
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if err != nil {
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return true, err
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}
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if change != nil {
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if err := e.benchmarkGerritChange(*change); err != nil {
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return true, err
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}
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return true, nil
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}
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}
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{
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log.Println("scanning for submitted changes to benchmark...")
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changesToBenchmark, err := e.changesToBenchmark()
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if err != nil {
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return true, err
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}
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if len(changesToBenchmark) > 0 {
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log.Printf("%v submitted changes to benchmark...", len(changesToBenchmark))
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start := time.Now()
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for i, c := range changesToBenchmark {
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if time.Since(start) > time.Minute*15 {
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// It's been a while since we scanned for review changes.
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// Take a break from benchmarking submitted changes so we
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// can scan for review changes to benchmark.
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log.Printf("benchmarked %v changes", i)
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return true, nil
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}
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benchRes, err := e.benchmarkTintChange(c.hash, c.desc)
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if err != nil {
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log.Printf("benchmarking failed: %v", err)
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benchRes = &bench.Run{}
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}
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commitRes, err := e.benchmarksToCommitResults(c.hash, *benchRes)
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if err != nil {
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return true, err
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}
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log.Printf("pushing results...")
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if err := e.pushUpdatedResults(*commitRes); err != nil {
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return true, err
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}
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}
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return true, nil
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}
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}
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{
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log.Println("scanning for benchmarks to refine...")
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changeToBenchmark, err := e.changeToRefineBenchmarks()
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if err != nil {
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return true, err
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}
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if changeToBenchmark != nil {
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log.Printf("re-benchmarking change '%v'", changeToBenchmark.hash)
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benchRes, err := e.benchmarkTintChange(changeToBenchmark.hash, changeToBenchmark.desc)
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if err != nil {
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log.Printf("benchmarking failed: %v", err)
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benchRes = &bench.Run{}
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}
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commitRes, err := e.benchmarksToCommitResults(changeToBenchmark.hash, *benchRes)
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if err != nil {
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return true, err
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}
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log.Printf("pushing results...")
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if err := e.pushUpdatedResults(*commitRes); err != nil {
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return true, err
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}
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return true, nil
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}
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}
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return false, nil
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}
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// HashAndDesc describes a single change to benchmark
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type HashAndDesc struct {
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hash git.Hash
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desc string
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}
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// changesToBenchmark fetches the list of changes that do not currently have
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// benchmark results, which should be benchmarked.
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func (e env) changesToBenchmark() ([]HashAndDesc, error) {
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log.Println("syncing dawn repo...")
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latest, err := e.dawnRepo.Fetch(e.cfg.Dawn.Branch, &git.FetchOptions{
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Credentials: e.cfg.Dawn.Credentials,
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})
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if err != nil {
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return nil, err
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}
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allChanges, err := e.dawnRepo.Log(&git.LogOptions{
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From: e.cfg.RootChange.String(),
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To: latest.String(),
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})
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if err != nil {
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return nil, fmt.Errorf("failed to obtain dawn log:\n %w", err)
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}
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changesWithBenchmarks, err := e.changesWithBenchmarks()
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if err != nil {
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return nil, fmt.Errorf("failed to gather changes with existing benchmarks:\n %w", err)
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}
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changesToBenchmark := make([]HashAndDesc, 0, len(allChanges))
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for _, c := range allChanges {
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if _, exists := changesWithBenchmarks[c.Hash]; !exists {
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changesToBenchmark = append(changesToBenchmark, HashAndDesc{c.Hash, c.Subject})
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}
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}
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// Reverse the order of changesToBenchmark, so that the oldest comes first.
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for i := len(changesToBenchmark)/2 - 1; i >= 0; i-- {
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j := len(changesToBenchmark) - 1 - i
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changesToBenchmark[i], changesToBenchmark[j] = changesToBenchmark[j], changesToBenchmark[i]
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}
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return changesToBenchmark, nil
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}
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// changeToRefineBenchmarks scans for the most suitable historic commit to
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// re-benchmark and refine the results. Returns nil if there are no suitable
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// changes.
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func (e env) changeToRefineBenchmarks() (*HashAndDesc, error) {
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log.Println("syncing results repo...")
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if err := fetchAndCheckoutLatest(e.resultsRepo, e.cfg.Results); err != nil {
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return nil, err
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}
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_, absPath, err := e.resultsFilePaths()
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if err != nil {
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return nil, err
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}
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results, err := e.loadHistoricResults(absPath)
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if err != nil {
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log.Println(fmt.Errorf("WARNING: failed to open result file '%v':\n %w", absPath, err))
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return nil, nil
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}
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if len(results.Commits) == 0 {
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return nil, nil
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}
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type changeDelta struct {
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change HashAndDesc
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delta float64
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}
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hashDeltas := make([]changeDelta, 0, len(results.Commits))
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for i, c := range results.Commits {
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hash, err := git.ParseHash(c.Commit)
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if err != nil {
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return nil, err
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}
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prev := results.Commits[max(0, i-1)]
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next := results.Commits[min(len(results.Commits)-1, i+1)]
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delta, count := 0.0, 0
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for _, b := range c.Benchmarks {
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if b.Time == 0 {
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continue
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}
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p, n := b.Time, b.Time
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if pb := prev.findBenchmark(b.Name); pb != nil {
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p = pb.Time
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}
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if nb := next.findBenchmark(b.Name); nb != nil {
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n = nb.Time
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}
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avr := (p + n) / 2
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confidence := math.Pow(2, float64(b.Repeats))
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delta += math.Abs(avr-b.Time) / (b.Time * confidence)
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count++
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}
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if count > 0 {
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delta = delta / float64(count)
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desc := strings.Split(c.CommitDescription, "\n")[0]
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hashDeltas = append(hashDeltas, changeDelta{HashAndDesc{hash, desc}, delta})
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}
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}
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sort.Slice(hashDeltas, func(i, j int) bool { return hashDeltas[i].delta > hashDeltas[j].delta })
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return &hashDeltas[0].change, nil
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}
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// benchmarkTintChangeIfNotCached first checks the results cache for existing
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// benchmark values for the given change, returning those cached values if hit.
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// If the cache does not contain results for the change, then
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// e.benchmarkTintChange() is called.
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func (e env) benchmarkTintChangeIfNotCached(hash git.Hash, desc string) (*bench.Run, error) {
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if cached, ok := e.benchmarkCache[hash]; ok {
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log.Printf("reusing cached benchmark results of '%v'...", hash)
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return cached, nil
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}
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return e.benchmarkTintChange(hash, desc)
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}
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// benchmarkTintChange checks out the given commit, fetches the dawn third party
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// dependencies, builds tint, then runs the benchmarks, returning the results.
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func (e env) benchmarkTintChange(hash git.Hash, desc string) (*bench.Run, error) {
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log.Printf("checking out dawn at '%v': %v...", hash, desc)
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if err := checkout(hash, e.dawnRepo); err != nil {
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return nil, err
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}
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log.Println("fetching dawn dependencies...")
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if err := e.fetchDawnDeps(); err != nil {
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return nil, err
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}
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log.Println("building tint...")
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if err := e.buildTint(); err != nil {
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return nil, err
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}
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if err := e.waitForTempsToSettle(); err != nil {
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return nil, err
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}
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log.Println("benchmarking tint...")
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run, err := e.repeatedlyBenchmarkTint()
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if err != nil {
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return nil, err
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}
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e.benchmarkCache[hash] = run
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return run, nil
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}
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|
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// benchmarksToCommitResults converts the benchmarks in the provided bench.Run
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// to a CommitResults.
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|
func (e env) benchmarksToCommitResults(hash git.Hash, results bench.Run) (*CommitResults, error) {
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commits, err := e.dawnRepo.Log(&git.LogOptions{
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From: hash.String(),
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})
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if err != nil || len(commits) == 0 {
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return nil, fmt.Errorf("failed to get commit object '%v' of dawn repo:\n %w", hash, err)
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}
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commit := commits[len(commits)-1]
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if commit.Hash != hash {
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panic(fmt.Errorf("git.Repository.Log({From: %v}) returned:\n%+v", hash, commits))
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}
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|
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m := map[string]Benchmark{}
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for _, b := range results.Benchmarks {
|
|
m[b.Name] = Benchmark{
|
|
Name: b.Name,
|
|
Time: float64(b.Duration) / float64(time.Second),
|
|
}
|
|
}
|
|
|
|
out := &CommitResults{
|
|
Commit: commit.Hash.String(),
|
|
CommitDescription: commit.Subject,
|
|
CommitTime: commit.Date,
|
|
Benchmarks: make([]Benchmark, 0, len(m)),
|
|
}
|
|
for _, b := range m {
|
|
out.Benchmarks = append(out.Benchmarks, b)
|
|
}
|
|
out.sort()
|
|
|
|
return out, nil
|
|
}
|
|
|
|
// changesWithBenchmarks returns a set of dawn changes that we already have
|
|
// benchmarks for.
|
|
func (e env) changesWithBenchmarks() (map[git.Hash]struct{}, error) {
|
|
log.Println("syncing results repo...")
|
|
if err := fetchAndCheckoutLatest(e.resultsRepo, e.cfg.Results); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
_, absPath, err := e.resultsFilePaths()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
results, err := e.loadHistoricResults(absPath)
|
|
if err != nil {
|
|
log.Println(fmt.Errorf("WARNING: failed to open result file '%v':\n %w", absPath, err))
|
|
return nil, nil
|
|
}
|
|
|
|
m := make(map[git.Hash]struct{}, len(results.Commits))
|
|
for _, c := range results.Commits {
|
|
hash, err := git.ParseHash(c.Commit)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
m[hash] = struct{}{}
|
|
}
|
|
return m, nil
|
|
}
|
|
|
|
// pushUpdatedResults fetches and loads the latest benchmark results, adds or
|
|
// merges the new results 'res' to the file, and then pushes the new results to
|
|
// the server.
|
|
func (e env) pushUpdatedResults(res CommitResults) error {
|
|
log.Println("syncing results repo...")
|
|
if err := fetchAndCheckoutLatest(e.resultsRepo, e.cfg.Results); err != nil {
|
|
return err
|
|
}
|
|
|
|
relPath, absPath, err := e.resultsFilePaths()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
h, err := e.loadHistoricResults(absPath)
|
|
if err != nil {
|
|
log.Println(fmt.Errorf("failed to open result file '%v'. Creating new file\n %w", absPath, err))
|
|
h = &HistoricResults{System: e.system}
|
|
}
|
|
|
|
// Are there existing benchmark results for this commit?
|
|
if existing := h.findCommitResults(res.Commit); existing != nil {
|
|
// Yes: merge in the new results
|
|
for _, b := range res.Benchmarks {
|
|
if e := existing.findBenchmark(b.Name); e != nil {
|
|
// Benchmark found to merge. Add a weighted contribution to the benchmark value.
|
|
e.Time = (e.Time*float64(e.Repeats+1) + b.Time) / float64(e.Repeats+2)
|
|
e.Repeats++
|
|
} else {
|
|
// New benchmark? Just append.
|
|
existing.Benchmarks = append(existing.Benchmarks, b)
|
|
}
|
|
}
|
|
existing.sort()
|
|
} else {
|
|
// New benchmark results for this commit. Just append.
|
|
h.Commits = append(h.Commits, res)
|
|
}
|
|
|
|
// Sort the commits by timestamp
|
|
h.sort()
|
|
|
|
// Write the new results to the file
|
|
f, err := os.Create(absPath)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to create updated results file '%v':\n %w", absPath, err)
|
|
}
|
|
defer f.Close()
|
|
|
|
enc := json.NewEncoder(f)
|
|
enc.SetIndent("", " ")
|
|
if err := enc.Encode(h); err != nil {
|
|
return fmt.Errorf("failed to encode updated results file '%v':\n %w", absPath, err)
|
|
}
|
|
|
|
// Stage the file
|
|
if err := e.resultsRepo.Add(relPath, nil); err != nil {
|
|
return fmt.Errorf("failed to stage updated results file '%v':\n %w", relPath, err)
|
|
}
|
|
|
|
// Commit the change
|
|
msg := fmt.Sprintf("Add benchmark results for '%v'", res.Commit[:6])
|
|
hash, err := e.resultsRepo.Commit(msg, &git.CommitOptions{
|
|
AuthorName: "tint perfmon bot",
|
|
AuthorEmail: "tint-perfmon-bot@gmail.com",
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf("failed to commit updated results file '%v':\n %w", absPath, err)
|
|
}
|
|
|
|
// Push the change
|
|
log.Println("pushing updated results to results repo...")
|
|
if err := e.resultsRepo.Push(hash.String(), e.cfg.Results.Branch, &git.PushOptions{
|
|
Credentials: e.cfg.Results.Credentials,
|
|
}); err != nil {
|
|
return fmt.Errorf("failed to push updated results file '%v':\n %w", absPath, err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// resultsFilePaths returns the paths to the results.json file, holding the
|
|
// benchmarks for the given system.
|
|
func (e env) resultsFilePaths() (relPath string, absPath string, err error) {
|
|
dir := filepath.Join(e.resultsDir, "results")
|
|
if err = os.MkdirAll(dir, 0777); err != nil {
|
|
err = fmt.Errorf("failed to create results directory '%v':\n %w", dir, err)
|
|
return
|
|
}
|
|
relPath = filepath.Join("results", e.systemID+".json")
|
|
absPath = filepath.Join(dir, e.systemID+".json")
|
|
return
|
|
}
|
|
|
|
// loadHistoricResults loads and returns the results.json file for the given
|
|
// system.
|
|
func (e env) loadHistoricResults(path string) (*HistoricResults, error) {
|
|
file, err := os.Open(path)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to open result file '%v':\n %w", path, err)
|
|
}
|
|
defer file.Close()
|
|
res := &HistoricResults{}
|
|
if err := json.NewDecoder(file).Decode(res); err != nil {
|
|
return nil, fmt.Errorf("failed to parse result file '%v':\n %w", path, err)
|
|
}
|
|
|
|
if !reflect.DeepEqual(res.System, e.system) {
|
|
log.Printf(`WARNING: results file '%v' has different system information!
|
|
File: %+v
|
|
System: %+v`, path, res.System, e.system)
|
|
}
|
|
|
|
return res, nil
|
|
}
|
|
|
|
// fetchDawnDeps fetches the third party dawn dependencies using gclient.
|
|
func (e env) fetchDawnDeps() error {
|
|
gclientConfig := filepath.Join(e.dawnDir, ".gclient")
|
|
if _, err := os.Stat(gclientConfig); errors.Is(err, os.ErrNotExist) {
|
|
standalone := filepath.Join(e.dawnDir, "scripts", "standalone.gclient")
|
|
if err := copyFile(gclientConfig, standalone); err != nil {
|
|
return fmt.Errorf("failed to copy '%v' to '%v':\n %w", standalone, gclientConfig, err)
|
|
}
|
|
}
|
|
if _, err := call(tools.gclient, e.dawnDir, e.cfg.Timeouts.Sync,
|
|
"sync",
|
|
"--force",
|
|
); err != nil {
|
|
return fmt.Errorf("failed to fetch dawn dependencies:\n %w", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// buildTint builds the tint benchmarks.
|
|
func (e env) buildTint() error {
|
|
if err := os.MkdirAll(e.buildDir, 0777); err != nil {
|
|
return fmt.Errorf("failed to create build directory at '%v':\n %w", e.buildDir, err)
|
|
}
|
|
if _, err := call(tools.cmake, e.buildDir, e.cfg.Timeouts.Build,
|
|
e.dawnDir,
|
|
"-GNinja",
|
|
"-DCMAKE_CXX_COMPILER_LAUNCHER=ccache",
|
|
"-DCMAKE_BUILD_TYPE=Release",
|
|
"-DCMAKE_BUILD_TESTS=0",
|
|
"-DCMAKE_BUILD_SAMPLES=0",
|
|
"-DTINT_EXTERNAL_BENCHMARK_CORPUS_DIR="+e.cfg.ExternalBenchmarkCorpus,
|
|
"-DTINT_BUILD_DOCS=0",
|
|
"-DTINT_BUILD_SAMPLES=0",
|
|
"-DTINT_BUILD_TESTS=0",
|
|
"-DTINT_BUILD_SPV_READER=1",
|
|
"-DTINT_BUILD_WGSL_READER=1",
|
|
"-DTINT_BUILD_GLSL_WRITER=1",
|
|
"-DTINT_BUILD_HLSL_WRITER=1",
|
|
"-DTINT_BUILD_MSL_WRITER=1",
|
|
"-DTINT_BUILD_SPV_WRITER=1",
|
|
"-DTINT_BUILD_WGSL_WRITER=1",
|
|
"-DTINT_BUILD_BENCHMARKS=1",
|
|
"-DDAWN_BUILD_SAMPLES=0",
|
|
); err != nil {
|
|
return errFailedToBuild{fmt.Errorf("failed to generate dawn build config:\n %w", err)}
|
|
}
|
|
if _, err := call(tools.ninja, e.buildDir, e.cfg.Timeouts.Build); err != nil {
|
|
return errFailedToBuild{err}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// errFailedToBuild is the error returned by buildTint() if the build failed
|
|
type errFailedToBuild struct {
|
|
// The reason
|
|
reason error
|
|
}
|
|
|
|
func (e errFailedToBuild) Error() string {
|
|
return fmt.Sprintf("failed to build: %v", e.reason)
|
|
}
|
|
|
|
// errFailedToBenchmark is the error returned by benchmarkTint() if the benchmark failed
|
|
type errFailedToBenchmark struct {
|
|
// The reason
|
|
reason error
|
|
}
|
|
|
|
func (e errFailedToBenchmark) Error() string {
|
|
return fmt.Sprintf("failed to benchmark: %v", e.reason)
|
|
}
|
|
|
|
// benchmarkTint runs the tint benchmarks e.cfg.BenchmarkRepetitions times,
|
|
// returning the median timing.
|
|
func (e env) repeatedlyBenchmarkTint() (*bench.Run, error) {
|
|
var ctx *bench.Context
|
|
testTimes := map[string][]time.Duration{}
|
|
for i := 0; i < e.cfg.BenchmarkRepetitions; i++ {
|
|
if err := e.waitForTempsToSettle(); err != nil {
|
|
return nil, err
|
|
}
|
|
log.Printf("benchmark pass %v/%v...", (i + 1), e.cfg.BenchmarkRepetitions)
|
|
run, err := e.benchmarkTint()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
for _, b := range run.Benchmarks {
|
|
testTimes[b.Name] = append(testTimes[b.Name], b.Duration)
|
|
}
|
|
if ctx == nil {
|
|
ctx = run.Context
|
|
}
|
|
}
|
|
|
|
out := bench.Run{Context: ctx}
|
|
for name, times := range testTimes {
|
|
sort.Slice(times, func(i, j int) bool { return times[i] < times[j] })
|
|
out.Benchmarks = append(out.Benchmarks, bench.Benchmark{
|
|
Name: name,
|
|
Duration: times[len(times)/2], // Median
|
|
})
|
|
}
|
|
|
|
return &out, nil
|
|
}
|
|
|
|
// benchmarkTint runs the tint benchmarks once, returning the results.
|
|
func (e env) benchmarkTint() (*bench.Run, error) {
|
|
exe := filepath.Join(e.buildDir, "tint-benchmark")
|
|
out, err := call(exe, e.buildDir, e.cfg.Timeouts.Benchmark,
|
|
"--benchmark_format=json",
|
|
"--benchmark_enable_random_interleaving=true",
|
|
)
|
|
if err != nil {
|
|
return nil, errFailedToBenchmark{fmt.Errorf("failed to run benchmarks: %w\noutput: %v", err, out)}
|
|
}
|
|
|
|
results, err := bench.Parse(out)
|
|
if err != nil {
|
|
return nil, errFailedToBenchmark{fmt.Errorf("failed to parse benchmark results: %w\noutput: %v", err, out)}
|
|
}
|
|
return &results, nil
|
|
}
|
|
|
|
// findGerritChangeToBenchmark queries gerrit for a change to benchmark.
|
|
func (e env) findGerritChangeToBenchmark() (*gerrit.ChangeInfo, error) {
|
|
log.Println("querying gerrit for changes...")
|
|
results, _, err := e.gerrit.Changes.QueryChanges(&gerrit.QueryChangeOptions{
|
|
QueryOptions: gerrit.QueryOptions{
|
|
Query: []string{"project:dawn status:open+-age:3d"},
|
|
Limit: 100,
|
|
},
|
|
ChangeOptions: gerrit.ChangeOptions{
|
|
AdditionalFields: []string{"CURRENT_REVISION", "CURRENT_COMMIT", "MESSAGES", "LABELS", "DETAILED_ACCOUNTS"},
|
|
},
|
|
})
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to get list of changes:\n %w", err)
|
|
}
|
|
|
|
type candidate struct {
|
|
change gerrit.ChangeInfo
|
|
priority int
|
|
}
|
|
|
|
candidates := make([]candidate, 0, len(*results))
|
|
|
|
for _, change := range *results {
|
|
kokoroApproved := change.Labels["Kokoro"].Approved.AccountID != 0
|
|
codeReviewScore := change.Labels["Code-Review"].Value
|
|
codeReviewApproved := change.Labels["Code-Review"].Approved.AccountID != 0
|
|
presubmitReady := change.Labels["Presubmit-Ready"].Approved.AccountID != 0
|
|
verifiedScore := change.Labels["Verified"].Value
|
|
|
|
current, ok := change.Revisions[change.CurrentRevision]
|
|
if !ok {
|
|
log.Printf("WARNING: couldn't find current revision for change '%s'", change.ChangeID)
|
|
}
|
|
|
|
canBenchmark := func() bool {
|
|
// Is the change from a Googler, reviewed by a Googler or is from a allow-listed external developer?
|
|
if !(strings.HasSuffix(current.Commit.Committer.Email, "@google.com") ||
|
|
strings.HasSuffix(change.Labels["Code-Review"].Approved.Email, "@google.com") ||
|
|
strings.HasSuffix(change.Labels["Code-Review"].Recommended.Email, "@google.com") ||
|
|
strings.HasSuffix(change.Labels["Presubmit-Ready"].Approved.Email, "@google.com")) {
|
|
permitted := false
|
|
for _, email := range e.cfg.ExternalAccounts {
|
|
if strings.EqualFold(current.Commit.Committer.Email, email) {
|
|
permitted = true
|
|
break
|
|
}
|
|
|
|
}
|
|
if !permitted {
|
|
return false
|
|
}
|
|
}
|
|
|
|
// Don't benchmark if the change has negative scores.
|
|
if codeReviewScore < 0 || verifiedScore < 0 {
|
|
return false
|
|
}
|
|
|
|
// Has the latest patchset already been benchmarked?
|
|
for _, msg := range change.Messages {
|
|
if msg.RevisionNumber == current.Number &&
|
|
msg.Author.Email == e.cfg.Gerrit.Email {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}()
|
|
if !canBenchmark {
|
|
continue
|
|
}
|
|
|
|
priority := 0
|
|
if presubmitReady {
|
|
priority += 10
|
|
}
|
|
priority += codeReviewScore
|
|
if codeReviewApproved {
|
|
priority += 2
|
|
}
|
|
if kokoroApproved {
|
|
priority++
|
|
}
|
|
|
|
candidates = append(candidates, candidate{change, priority})
|
|
}
|
|
|
|
// Sort the candidates
|
|
sort.Slice(candidates, func(i, j int) bool {
|
|
return candidates[i].priority > candidates[j].priority
|
|
})
|
|
|
|
if len(candidates) > 0 {
|
|
log.Printf("%d gerrit changes to benchmark", len(candidates))
|
|
return &candidates[0].change, nil
|
|
}
|
|
return nil, nil
|
|
}
|
|
|
|
// benchmarks the gerrit change, posting the findings to the change
|
|
func (e env) benchmarkGerritChange(change gerrit.ChangeInfo) error {
|
|
current := change.Revisions[change.CurrentRevision]
|
|
fmt.Println("benchmarking", change.URL)
|
|
log.Printf("fetching '%v'...", current.Ref)
|
|
currentHash, err := e.dawnRepo.Fetch(current.Ref, &git.FetchOptions{
|
|
Credentials: e.cfg.Dawn.Credentials,
|
|
})
|
|
if err != nil {
|
|
return err
|
|
}
|
|
parent := current.Commit.Parents[0]
|
|
parentHash, err := git.ParseHash(parent.Commit)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to parse parent hash '%v':\n %v", parent, err)
|
|
}
|
|
|
|
postMsg := func(notify, msg string) error {
|
|
_, _, err = e.gerrit.Changes.SetReview(change.ChangeID, currentHash.String(), &gerrit.ReviewInput{
|
|
Message: msg,
|
|
Tag: "autogenerated:perfmon",
|
|
Notify: notify,
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf("failed to post message to gerrit change:\n %v", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
newRun, err := e.benchmarkTintChange(currentHash, change.Subject)
|
|
if err != nil {
|
|
log.Printf("ERROR: %v", err)
|
|
buildErr := errFailedToBuild{}
|
|
if errors.As(err, &buildErr) {
|
|
return postMsg("OWNER", fmt.Sprintf("patchset %v failed to build", current.Number))
|
|
}
|
|
benchErr := errFailedToBenchmark{}
|
|
if errors.As(err, &benchErr) {
|
|
return postMsg("OWNER", fmt.Sprintf("patchset %v failed to benchmark", current.Number))
|
|
}
|
|
return err
|
|
}
|
|
if _, err := e.dawnRepo.Fetch(parent.Commit, &git.FetchOptions{
|
|
Credentials: e.cfg.Dawn.Credentials,
|
|
}); err != nil {
|
|
return err
|
|
}
|
|
parentRun, err := e.benchmarkTintChangeIfNotCached(parentHash,
|
|
fmt.Sprintf("[parent of %v] %v", currentHash.String()[:7], parent.Subject))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
const minDiff = time.Microsecond * 50 // Ignore time diffs less than this duration
|
|
const minRelDiff = 0.01 // Ignore absolute relative diffs between [1, 1+x]
|
|
diff := bench.Compare(parentRun.Benchmarks, newRun.Benchmarks, minDiff, minRelDiff)
|
|
diffFmt := bench.DiffFormat{
|
|
TestName: true,
|
|
Delta: true,
|
|
PercentChangeAB: true,
|
|
TimeA: true,
|
|
TimeB: true,
|
|
}
|
|
|
|
msg := &strings.Builder{}
|
|
fmt.Fprintln(msg, "Perfmon analysis:")
|
|
fmt.Fprintln(msg)
|
|
fmt.Fprintln(msg, "```")
|
|
fmt.Fprintf(msg, "A: parent change (%v) -> B: patchset %v\n", parent.Commit[:7], current.Number)
|
|
fmt.Fprintln(msg)
|
|
for _, line := range strings.Split(diff.Format(diffFmt), "\n") {
|
|
fmt.Fprintf(msg, " %v\n", line)
|
|
}
|
|
fmt.Fprintln(msg, "```")
|
|
|
|
notify := "OWNER"
|
|
if len(diff) > 0 {
|
|
notify = "OWNER_REVIEWERS"
|
|
}
|
|
return postMsg(notify, msg.String())
|
|
}
|
|
|
|
// waitForTempsToSettle waits for the maximum temperature of all sensors to drop
|
|
// below the threshold value specified by the config.
|
|
func (e env) waitForTempsToSettle() error {
|
|
if e.cfg.CPUTempSensorName == "" {
|
|
time.Sleep(time.Second * 30)
|
|
return nil
|
|
}
|
|
const timeout = 5 * time.Minute
|
|
start := time.Now()
|
|
for {
|
|
temp, err := maxTemp(e.cfg.CPUTempSensorName)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to obtain system temeratures: %v", err)
|
|
}
|
|
if temp < e.cfg.BenchmarkMaxTemp {
|
|
log.Printf("temperatures settled. current: %v°C", temp)
|
|
return nil
|
|
}
|
|
if time.Since(start) > timeout {
|
|
log.Printf("timeout waiting for temperatures to settle. current: %v°C", temp)
|
|
return nil
|
|
}
|
|
log.Printf("waiting for temperatures to settle. current: %v°C, max: %v°C", temp, e.cfg.BenchmarkMaxTemp)
|
|
time.Sleep(time.Second * 10)
|
|
}
|
|
}
|
|
|
|
// createOrOpenGitRepo creates a new local repo by cloning cfg.URL into
|
|
// filepath, or opens the existing repo at filepath.
|
|
func createOrOpenGitRepo(g *git.Git, filepath string, cfg GitConfig) (*git.Repository, error) {
|
|
repo, err := g.Open(filepath)
|
|
if errors.Is(err, git.ErrRepositoryDoesNotExist) {
|
|
log.Printf("cloning '%v' branch '%v' to '%v'...", cfg.URL, cfg.Branch, filepath)
|
|
repo, err = g.Clone(filepath, cfg.URL, &git.CloneOptions{
|
|
Branch: cfg.Branch,
|
|
Credentials: cfg.Credentials,
|
|
})
|
|
}
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to open git repository '%v':\n %w", filepath, err)
|
|
}
|
|
return repo, err
|
|
}
|
|
|
|
// loadConfig loads the perfmon config file.
|
|
func loadConfig(path string) (Config, error) {
|
|
f, err := os.Open(path)
|
|
if err != nil {
|
|
return Config{}, fmt.Errorf("failed to open config file at '%v':\n %w", path, err)
|
|
}
|
|
cfg := Config{}
|
|
if err := json.NewDecoder(f).Decode(&cfg); err != nil {
|
|
return Config{}, fmt.Errorf("failed to load config file at '%v':\n %w", path, err)
|
|
}
|
|
cfg.setDefaults()
|
|
return cfg, nil
|
|
}
|
|
|
|
// makeWorkingDirs creates the dawn repo and results repo directories.
|
|
func makeWorkingDirs(cfg Config) (dawnDir, resultsDir string, err error) {
|
|
wd, err := expandHomeDir(cfg.WorkingDir)
|
|
if err != nil {
|
|
return "", "", err
|
|
}
|
|
if err := os.MkdirAll(wd, 0777); err != nil {
|
|
return "", "", fmt.Errorf("failed to create working directory '%v':\n %w", wd, err)
|
|
}
|
|
dawnDir = filepath.Join(wd, "dawn")
|
|
if err := os.MkdirAll(dawnDir, 0777); err != nil {
|
|
return "", "", fmt.Errorf("failed to create working dawn directory '%v':\n %w", dawnDir, err)
|
|
}
|
|
resultsDir = filepath.Join(wd, "results")
|
|
if err := os.MkdirAll(resultsDir, 0777); err != nil {
|
|
return "", "", fmt.Errorf("failed to create working results directory '%v':\n %w", resultsDir, err)
|
|
}
|
|
return dawnDir, resultsDir, nil
|
|
}
|
|
|
|
// fetchAndCheckoutLatest calls fetch(cfg.Branch) followed by checkoutLatest().
|
|
func fetchAndCheckoutLatest(repo *git.Repository, cfg GitConfig) error {
|
|
hash, err := repo.Fetch(cfg.Branch, &git.FetchOptions{
|
|
Credentials: cfg.Credentials,
|
|
})
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if err := repo.Checkout(hash.String(), nil); err != nil {
|
|
return err
|
|
}
|
|
return checkout(hash, repo)
|
|
}
|
|
|
|
// checkout checks out the change with the given hash.
|
|
// Note: call fetch() to ensure that this is the latest change on the
|
|
// branch.
|
|
func checkout(hash git.Hash, repo *git.Repository) error {
|
|
if err := repo.Checkout(hash.String(), nil); err != nil {
|
|
return fmt.Errorf("failed to checkout '%v':\n %w", hash, err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// expandHomeDir returns path with all occurrences of '~' replaced with the user
|
|
// home directory.
|
|
func expandHomeDir(path string) (string, error) {
|
|
if strings.ContainsRune(path, '~') {
|
|
home, err := os.UserHomeDir()
|
|
if err != nil {
|
|
return "", fmt.Errorf("failed to expand home dir:\n %w", err)
|
|
}
|
|
path = strings.ReplaceAll(path, "~", home)
|
|
}
|
|
return path, nil
|
|
}
|
|
|
|
// tools holds the file paths to the executables used by this tool
|
|
var tools struct {
|
|
ccache string
|
|
cmake string
|
|
gclient string
|
|
git string
|
|
ninja string
|
|
sensors string
|
|
}
|
|
|
|
// findTools looks for the file paths for executables used by this tool,
|
|
// returning an error if any could not be found.
|
|
func findTools() error {
|
|
for _, tool := range []struct {
|
|
name string
|
|
path *string
|
|
}{
|
|
{"ccache", &tools.ccache},
|
|
{"cmake", &tools.cmake},
|
|
{"gclient", &tools.gclient},
|
|
{"git", &tools.git},
|
|
{"ninja", &tools.ninja},
|
|
{"sensors", &tools.sensors},
|
|
} {
|
|
path, err := exec.LookPath(tool.name)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to find path to '%v':\n %w", tool.name, err)
|
|
}
|
|
*tool.path = path
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// copyFile copies the file at srcPath to dstPath.
|
|
func copyFile(dstPath, srcPath string) error {
|
|
src, err := os.Open(srcPath)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to open file '%v':\n %w", srcPath, err)
|
|
}
|
|
defer src.Close()
|
|
dst, err := os.Create(dstPath)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to create file '%v':\n %w", dstPath, err)
|
|
}
|
|
defer dst.Close()
|
|
_, err = io.Copy(dst, src)
|
|
return err
|
|
}
|
|
|
|
// The regular expression to parse a temperature from 'sensors'
|
|
var reTemp = regexp.MustCompile("([0-9]+.[0-9])°C")
|
|
|
|
// maxTemp returns the maximum sensor temperature in celsius returned by 'sensors'
|
|
func maxTemp(sensorName string) (float32, error) {
|
|
output, err := call(tools.sensors, "", time.Second*2, sensorName)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
var maxTemp float32
|
|
for _, match := range reTemp.FindAllStringSubmatch(output, -1) {
|
|
var temp float32
|
|
if _, err := fmt.Sscanf(match[1], "%f", &temp); err == nil {
|
|
if temp > maxTemp {
|
|
maxTemp = temp
|
|
}
|
|
}
|
|
}
|
|
return maxTemp, nil
|
|
}
|
|
|
|
// call invokes the executable exe in the current working directory wd, with
|
|
// the provided arguments.
|
|
// If the executable does not complete within the timeout duration, then an
|
|
// error is returned.
|
|
func call(exe, wd string, timeout time.Duration, args ...string) (string, error) {
|
|
ctx, cancel := context.WithTimeout(context.Background(), timeout)
|
|
defer cancel()
|
|
args = append([]string{"-n", "-20", exe}, args...)
|
|
cmd := exec.CommandContext(ctx, "nice", args...)
|
|
cmd.Dir = wd
|
|
out, err := cmd.CombinedOutput()
|
|
if err != nil {
|
|
// Note: If you get a permission error with 'nice', then you either need
|
|
// to run as sudo (not recommended), or update your ulimits:
|
|
// Append to /etc/security/limits.conf:
|
|
// <user> - nice -20
|
|
return string(out), fmt.Errorf("'%v %v' failed:\n %w\n%v", exe, args, err, string(out))
|
|
}
|
|
return string(out), nil
|
|
}
|
|
|
|
// hash returns a hash of the string representation of 'o'.
|
|
func hash(o interface{}) string {
|
|
str := fmt.Sprintf("%+v", o)
|
|
hash := sha256.New()
|
|
hash.Write([]byte(str))
|
|
return hex.EncodeToString(hash.Sum(nil))[:8]
|
|
}
|
|
|
|
func min(a, b int) int {
|
|
if a < b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|
|
|
|
func max(a, b int) int {
|
|
if a > b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|