cmemprof

Documentation

Overview

Package cmemprof profiles C memory allocations (malloc, calloc, realloc, etc.)

Importing this package in a program will replace malloc, calloc, and realloc with wrappers which will sample allocations and record them to a profile.

To use this package:

f, _ := os.Create("cmem.pprof")
var profiler cmemprof.Profile
profiler.Start(500)
// ... do allocations
profile, err := profiler.Stop()

Building this package on Linux requires a non-standard linker flag to wrap the alloaction functions. For Go versions < 1.15, cgo won't allow the flag so it has to be explicitly allowed by setting the following environment variable when building a program that uses this package:

export CGO_LDFLAGS_ALLOW="-Wl,--wrap=.*"

Index

• type Profile
  • func (c *Profile) Start(rate int)
  • func (c *Profile) Stop() (*profile.Profile, error)

Types

type Profile

type Profile struct {

	// SamplingRate is the value, in bytes, such that an average of one
	// sample will be recorded for every SamplingRate bytes allocated.  An
	// allocation of N bytes will be recorded with probability min(1, N /
	// SamplingRate).
	SamplingRate int
	// contains filtered or unexported fields
}

Profile provides access to a C memory allocation profiler based on instrumenting malloc, calloc, and realloc.

func (*Profile) Start

func (c *Profile) Start(rate int)

Start begins profiling C memory allocations.

func (*Profile) Stop

func (c *Profile) Stop() (*profile.Profile, error)

Stop cancels memory profiling and waits for the profile to be written to the io.Writer passed to Start. Returns any error from writing the profile.