lotus/cmd/lotus-sim/profile.go
2021-06-18 15:44:35 -07:00

88 lines
1.7 KiB
Go

package main
import (
"archive/tar"
"context"
"fmt"
"io"
"os"
"os/signal"
"runtime/pprof"
"time"
"github.com/urfave/cli/v2"
)
func takeProfiles(ctx context.Context) (fname string, _err error) {
file, err := os.CreateTemp(".", ".profiles*.tar")
if err != nil {
return "", err
}
defer file.Close()
if err := writeProfiles(ctx, file); err != nil {
_ = os.Remove(file.Name())
return "", err
}
fname = fmt.Sprintf("pprof-simulation-%s.tar", time.Now())
if err := os.Rename(file.Name(), fname); err != nil {
_ = os.Remove(file.Name())
return "", err
}
return fname, nil
}
func writeProfiles(ctx context.Context, w io.Writer) error {
tw := tar.NewWriter(w)
for _, profile := range pprof.Profiles() {
if err := tw.WriteHeader(&tar.Header{Name: profile.Name()}); err != nil {
return err
}
if err := profile.WriteTo(tw, 0); err != nil {
return err
}
if err := ctx.Err(); err != nil {
return err
}
}
if err := tw.WriteHeader(&tar.Header{Name: "cpu"}); err != nil {
return err
}
if err := pprof.StartCPUProfile(tw); err != nil {
return err
}
select {
case <-time.After(30 * time.Second):
case <-ctx.Done():
pprof.StopCPUProfile()
return ctx.Err()
}
pprof.StopCPUProfile()
return tw.Close()
}
func profileOnSignal(cctx *cli.Context, signals ...os.Signal) {
ch := make(chan os.Signal, 1)
signal.Notify(ch, signals...)
defer signal.Stop(ch)
for {
select {
case <-ch:
fname, err := takeProfiles(cctx.Context)
switch err {
case context.Canceled:
return
case nil:
fmt.Fprintf(cctx.App.ErrWriter, "Wrote profile to %q\n", fname)
default:
fmt.Fprintf(cctx.App.ErrWriter, "ERROR: failed to write profile: %s\n", err)
}
case <-cctx.Done():
return
}
}
}