Mercurial > hg
view contrib/catapipe.py @ 44861:065421e12248
files: speed up `hg files` when no flags change display
It's not the first time I see slowness from this command slow down
tools built on top of hg.
The majority of the time is spent merely printing the result before
this change, which is clearly not how it should be (especially since
the computation of the result also looks slow).
Running `hg files` in mozilla-central:
parent revision: 1,260s
this commit: 0,683s
this commit without batching ui.write: 0,931s
this commit replacing the body of the loop with `pass`: 0,566s
This looks like a prime candidate for a rust fast path, but until
then, it seems reasonable to optimize the python.
Differential Revision: https://phab.mercurial-scm.org/D8586
author | Valentin Gatien-Baron <valentin.gatienbaron@gmail.com> |
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date | Tue, 26 May 2020 08:15:09 -0400 |
parents | 2372284d9457 |
children | 6000f5b25c9b |
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#!/usr/bin/env python3 # # Copyright 2018 Google LLC. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """Tool read primitive events from a pipe to produce a catapult trace. Usage: Terminal 1: $ catapipe.py /tmp/mypipe /tmp/trace.json Terminal 2: $ HGCATAPULTSERVERPIPE=/tmp/mypipe hg root <ctrl-c catapipe.py in Terminal 1> $ catapult/tracing/bin/trace2html /tmp/trace.json # produce /tmp/trace.html <open trace.html in your browser of choice; the WASD keys are very useful> (catapult is located at https://github.com/catapult-project/catapult) For now the event stream supports START $SESSIONID ... and END $SESSIONID ... events. Everything after the SESSIONID (which must not contain spaces) is used as a label for the event. Events are timestamped as of when they arrive in this process and are then used to produce catapult traces that can be loaded in Chrome's about:tracing utility. It's important that the event stream *into* this process stay simple, because we have to emit it from the shell scripts produced by run-tests.py. Typically you'll want to place the path to the named pipe in the HGCATAPULTSERVERPIPE environment variable, which both run-tests and hg understand. To trace *only* run-tests, use HGTESTCATAPULTSERVERPIPE instead. """ from __future__ import absolute_import, print_function import argparse import json import os import timeit _TYPEMAP = { 'START': 'B', 'END': 'E', 'COUNTER': 'C', } _threadmap = {} # Timeit already contains the whole logic about which timer to use based on # Python version and OS timer = timeit.default_timer def main(): parser = argparse.ArgumentParser() parser.add_argument( 'pipe', type=str, nargs=1, help='Path of named pipe to create and listen on.', ) parser.add_argument( 'output', default='trace.json', type=str, nargs='?', help='Path of json file to create where the traces ' 'will be stored.', ) parser.add_argument( '--debug', default=False, action='store_true', help='Print useful debug messages', ) args = parser.parse_args() fn = args.pipe[0] os.mkfifo(fn) try: with open(fn) as f, open(args.output, 'w') as out: out.write('[\n') start = timer() while True: ev = f.readline().strip() if not ev: continue now = timer() if args.debug: print(ev) verb, session, label = ev.split(' ', 2) if session not in _threadmap: _threadmap[session] = len(_threadmap) if verb == 'COUNTER': amount, label = label.split(' ', 1) payload_args = {'value': int(amount)} else: payload_args = {} pid = _threadmap[session] ts_micros = (now - start) * 1000000 out.write( json.dumps( { "name": label, "cat": "misc", "ph": _TYPEMAP[verb], "ts": ts_micros, "pid": pid, "tid": 1, "args": payload_args, } ) ) out.write(',\n') finally: os.unlink(fn) if __name__ == '__main__': main()