martin-helmich/prometheus-nginxlog-exporter

/*
 * Copyright 2019 Martin Helmich <martin@helmich.me>
 *
 * 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 prof

import (
    "fmt"
    "os"
    "runtime"
    "runtime/pprof"
    "sync"
)

// SetupMemoryProfiling starts memory profiling if an outputFile is specified
func SetupMemoryProfiling(outputFile string, stopChan <-chan bool, stopHandlers *sync.WaitGroup) {
    if outputFile == "" {
        return
    }

    runtime.MemProfileRate = 1
    stopHandlers.Add(1)

    go func() {
        <-stopChan

        f, err := os.Create(outputFile)
        if err != nil {
            panic(err)
        }

        fmt.Printf("writing memory profile to file %s\n", outputFile)

        runtime.GC()
        if err := pprof.WriteHeapProfile(f); err != nil {
            panic(err)
        }

        f.Close()
        stopHandlers.Done()
    }()
}