The developer docs: ; The output of go tool pprof –help (I pasted the output on my. Step #5: run go tool pprof. Pass your binary location, and the location of the cpu. pprof file as returned when running your program. You can. To build and install it, use the go get tool. go get -u Remember to set GOPATH to the directory where you want pprof to be installed.
||6 September 2006
|PDF File Size:
|ePub File Size:
||Free* [*Free Regsitration Required]
pprof – The Go Programming Language
See the diff from havlak2. The related command disasm shows a disassembly of the function instead of a source listing; when there are enough samples this can help you see which instructions are expensive. There is also a standard HTTP interface to profiling data. Then when it comes time to analyze your memory usage, you can decide where you want inuse memory or total allocation counts! There is also a standard HTTP interface to profiling data.
Context func ForLabels ctx context. Context, labels LabelSet context. To use pprof, link this package into your program: WriteHeapProfile is shorthand for Lookup “heap”. When I started working with pprof I was confused about what was actually happening.
It looks like the current bottleneck is the same as the last one: The normal way to use pprof seems to be: See the diff between havlak1 and havlak2. Add panics if the profile already contains a stack for value. Context, key string string, bool func SetGoroutineLabels ctx context.
The third column shows the running total during the listing: The augmented label map will be set for the duration of the call to f and restored once f returns. Add stores value in an internal map, so value must be suitable for use as a map key and will not be garbage collected until the corresponding call to Remove.
Commonly used commands include “top”, which prints a summary of the top program hot-spots, and “web”, which opens an interactive graph of hot-spots and pporf call graphs. If a profile with that name already exists, NewProfile panics. Labels og an even number of strings representing key-value pairs and makes a LabelSet containing them. The CPU profile is not available as a Profile. In ttool this post on custom pprof profile types and this on the newish profile type for seeing contended mutexes are great.
Profiling a Go program The first step to profiling a Go program is to enable profiling. It is preserved gk backwards compatibility. The first two columns show the number of samples in which the function was running as opposed to waiting for a called function to returnas a raw count and as a percentage of total samples.
The profiler requires a final call to StopCPUProfile to flush any pending writes to the file before the program exits; we use defer to make sure this toool as main returns. The final version of the Go program will use a separate LoopFinder instance to track this memory, restoring the possibility of concurrent use. This basically tells us that main.
Symbol looks up the program counters listed in the request, responding with a table mapping program counters to function names. The listing shows goo source code for the DFS function really, for every function matching the regular expression DFS.
Profiling Go programs with pprof
For example, the following command runs benchmarks in the current directory and writes the CPU and memory profiles to cpu. To view all available profiles, open http: The package is typically only imported for the side effect of registering its HTTP handlers.
There may be non-exported or anonymous functions among them if they are called dynamically from another package. This contains 1 sample.
Profiling Go Programs – The Go Blog
That explains the on the self-edge from main. What are locations 1 and 2? A Profile is a collection of stack traces showing the call sequences that led to instances of a particular event, such as allocation. The profile has samples, so it was running for a bit over 25 seconds. The programs are run on a computer with a 3. You can read the source for the memory profiler here: The output of this is a bit long, you can view it all here: Writer, debug int error Bugs.