hermes/backend/backendutil/profiling_enabled.go

91 lines
2.3 KiB
Go

//go:build debug
package backendutil
import (
"errors"
"fmt"
"os"
"os/signal"
"runtime/pprof"
"syscall"
"time"
"github.com/charmbracelet/log"
"golang.org/x/exp/rand"
)
func ConfigureProfiling() error {
profilingMode, err := os.ReadFile("/tmp/hermes.backendlauncher.profilebackends")
if err != nil && errors.Is(err, os.ErrNotExist) {
return nil
}
switch string(profilingMode) {
case "cpu":
log.Debug("Starting CPU profiling as a background task")
go doCPUProfiling()
case "mem":
log.Debug("Starting memory profiling as a background task")
go doMemoryProfiling()
default:
log.Warnf("Unknown profiling mode: %s", string(profilingMode))
return nil
}
return nil
}
func doCPUProfiling() {
// (imterah) WTF? why isn't this being seeded on its own? according to Go docs, this should be seeded automatically...
rand.Seed(uint64(time.Now().UnixNano()))
profileFileName := fmt.Sprintf("/tmp/hermes.backendlauncher.cpu.prof.%d", rand.Int())
profileFile, err := os.Create(profileFileName)
if err != nil {
log.Fatalf("Failed to create CPU profiling file: %s", err.Error())
}
log.Debugf("Writing CPU usage profile to '%s'. Will capture when Ctrl+C/SIGTERM is recieved.", profileFileName)
pprof.StartCPUProfile(profileFile)
exitNotification := make(chan os.Signal, 1)
signal.Notify(exitNotification, os.Interrupt, syscall.SIGTERM)
<-exitNotification
log.Debug("Recieved SIGTERM. Cleaning up and exiting...")
pprof.StopCPUProfile()
profileFile.Close()
log.Debug("Exiting...")
os.Exit(0)
}
func doMemoryProfiling() {
// (imterah) WTF? why isn't this being seeded on its own? according to Go docs, this should be seeded automatically...
rand.Seed(uint64(time.Now().UnixNano()))
profileFileName := fmt.Sprintf("/tmp/hermes.backendlauncher.mem.prof.%d", rand.Int())
profileFile, err := os.Create(profileFileName)
if err != nil {
log.Fatalf("Failed to create memory profiling file: %s", err.Error())
}
log.Debugf("Writing memory profile to '%s'. Will capture when Ctrl+C/SIGTERM is recieved.", profileFileName)
exitNotification := make(chan os.Signal, 1)
signal.Notify(exitNotification, os.Interrupt, syscall.SIGTERM)
<-exitNotification
log.Debug("Recieved SIGTERM. Cleaning up and exiting...")
pprof.WriteHeapProfile(profileFile)
profileFile.Close()
log.Debug("Exiting...")
os.Exit(0)
}