Tool for stochastically profiling Go programs. Collects stack traces and synthesizes them into a flame graph. Uses Go's built in pprof library.
Example Flame Graph
$ go-torch --help NAME: go-torch - go-torch collects stack traces of a Go application and synthesizes them into into a [flame graph](http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html) USAGE: go-torch [global options] command [command options] [arguments...] COMMANDS: help, h Shows a list of commands or help for one command GLOBAL OPTIONS: --url, -u "http://localhost:8080" base url of your Go program --suffix, -s "/debug/pprof/profile" url path of pprof profile --binaryinput, -b file path of raw binary profile; alternative to having go-torch query pprof endpoint (binary profile is anything accepted by https://golang.org/cmd/pprof) --binaryname file path of the binary that the binaryinput is for, used for pprof inputs --time, -t "30" time in seconds to profile for --file, -f "torch.svg" ouput file name (must be .svg) --print, -p print the generated svg to stdout instead of writing to file --raw, -r print the raw call graph output to stdout instead of creating a flame graph; use with Brendan Gregg's flame graph perl script (see https://github.com/brendangregg/FlameGraph) --title graph title to display in the output file --help, -h show help --version, -v print the version
$ go-torch --time=15 --file "torch.svg" --url http://localhost:8080 INFO Profiling ... INFO flame graph has been created as torch.svg
$ go-torch --time=15 --print --url http://localhost:8080 INFO Profiling ... <svg> ... </svg> INFO flame graph has been printed to stdout
$ go-torch --time=15 --raw --url http://localhost:8080 INFO Profiling ... function1;function2 3 ... INFO raw call graph output been printed to stdout
Local pprof Example
$ go test -cpuprofile=cpu.pprof # This creates a cpu.pprof file, and the golang.test binary. $ go-torch --binaryinput cpu.pprof --binaryname golang.test INFO Profiling ... INFO flame graph has been created as torch.svg
$ go get github.com/uber/go-torch
You can also use go-torch using docker:
$ docker run uber/go-torch -u http://[address-of-host] -p > torch.svg
-p will print the SVG to standard out, which can then be redirected
to a file. This avoids mounting volumes to a container.
Install the Go dependencies:
$ go get github.com/Masterminds/glide $ glide install
Get the flame graph script:
$ git clone https://github.com/brendangregg/FlameGraph.git
Integrating With Your Application
Expose a pprof endpoint. Official Go docs are here. If your application is already running a server on the DefaultServeMux, just add this import to your application.
import _ "net/http/pprof"
If your application is not using the DefaultServeMux, you can still easily expose pprof endpoints by manually registering the net/http/pprof handlers or by using a library like this one.
Run the Tests
$ go test ./... ok github.com/uber/go-torch 0.012s ok github.com/uber/go-torch/graph 0.017s ok github.com/uber/go-torch/visualization 0.052s