memprofile-loop.go

func MemProfiler() {
      // record memory profile on a loop
      ticker := time.NewTicker(time.Second)

      for {
              <-ticker.C
              st := &runtime.MemStats{}
              runtime.ReadMemStats(st)
              // From Golang docs: HeapObjects increases as objects are allocated
              // and decreases as the heap is swept and unreachable objects are
              // freed.
              /*
                      fmt.Println("Heap allocs:", st.Mallocs, "Heap frees:",
                              st.Frees, "Heap objects:", st.HeapObjects)
              */

              // REVIEW: couldn't figure out how to collect multiple profiles in the same file
              if f, err := os.Create(fmt.Sprintf("factomd.%v.memprof", time.Now().UnixNano())); err != nil {
                      fmt.Printf("record memory profile failed: %v", err)
              } else {
                      runtime.GC() // trigger garbage collection first
                      pprof.WriteHeapProfile(f)
                      f.Close()
                      //fmt.Println("record memory profile")
              }

      }
}