gops/README.md

# gops

gops is a command to list and diagnose Go processes currently running on your system.

```
$ gops
983     uplink-soecks	(/usr/local/bin/uplink-soecks)
52697   gops	(/Users/jbd/bin/gops)
51130   gocode	(/Users/jbd/bin/gocode)
```

## Installation

```
$ go get -u github.com/google/gops
```

## Diagnostics

For processes that imports the diagnostics agent, the tool can report
additional information such as the current stack trace, Go version, memory
stats, etc.

Diagnostics features are only supported on Unix-like systems for now.

### stack
Prints the stack trace for the process identified with the specified PID.
```
$ gops stack -p=<pid>
goroutine 35 [running]:
github.com/google/gops/agent.handle(0x11897a0, 0xc4200d0000, 0xc4200c6000, 0x1, 0x1, 0x0, 0x0)
	/Users/jbd/src/github.com/google/gops/agent/agent.go:63 +0x182
github.com/google/gops/agent.init.1.func2(0x1189140, 0xc420078450)
	/Users/jbd/src/github.com/google/gops/agent/agent.go:50 +0x242
created by github.com/google/gops/agent.init.1
	/Users/jbd/src/github.com/google/gops/agent/agent.go:56 +0x240

goroutine 1 [sleep]:
time.Sleep(0x34630b8a000)
	/Users/jbd/go/src/runtime/time.go:59 +0xf7
main.main()
	/Users/jbd/src/github.com/google/gops/examples/hello/main.go:14 +0x30

goroutine 17 [syscall, locked to thread]:
runtime.goexit()
	/Users/jbd/go/src/runtime/asm_amd64.s:2184 +0x1

goroutine 20 [syscall]:
os/signal.signal_recv(0x0)
	/Users/jbd/go/src/runtime/sigqueue.go:116 +0xff
os/signal.loop()
	/Users/jbd/go/src/os/signal/signal_unix.go:22 +0x22
created by os/signal.init.1
	/Users/jbd/go/src/os/signal/signal_unix.go:28 +0x41

goroutine 21 [select, locked to thread]:
runtime.gopark(0x1114a80, 0x0, 0x110d5ec, 0x6, 0x18, 0x2)
	/Users/jbd/go/src/runtime/proc.go:261 +0x13a
runtime.selectgoImpl(0xc42003ff50, 0x0, 0x18)
	/Users/jbd/go/src/runtime/select.go:423 +0x1307
runtime.selectgo(0xc42003ff50)
	/Users/jbd/go/src/runtime/select.go:238 +0x1c
runtime.ensureSigM.func1()
	/Users/jbd/go/src/runtime/signal_unix.go:408 +0x265
runtime.goexit()
	/Users/jbd/go/src/runtime/asm_amd64.s:2184 +0x1

goroutine 34 [chan receive]:
github.com/google/gops/agent.init.1.func1(0xc4200740c0, 0xc4200880e0, 0x13)
	/Users/jbd/src/github.com/google/gops/agent/agent.go:33 +0x40
created by github.com/google/gops/agent.init.1
	/Users/jbd/src/github.com/google/gops/agent/agent.go:36 +0x214
```

## gc

Runs garbage collector and blocks until the garbage collection is completed.

```
$ gops gc -p=<pid>
```

## memstats

Reports the memory stats from the targetted Go process.

```
$ gops memstats -p=<pid>
alloc: 219792
total-alloc: 219792
sys: 2822144
lookups: 9
mallocs: 336
frees: 8
heap-alloc: 219792
heap-sys: 1605632
heap-idle: 1015808
heap-in-use: 589824
heap-released: 0
heap-objects: 328
stack-in-use: 491520
stack-sys: 491520
next-gc: 4473924
last-gc: 0 ns ago
gc-pause: 0 ns
num-gc: 0
enable-gc: true
debug-gc: false
```

## version

Reports the Go version used to build the target program.

```
$ gops version -p=<pid>
devel +4141054 Thu Nov 3 17:42:01 2016 +0000
```