Mercurial > hg
view contrib/debugcmdserver.py @ 23343:f8a2647fe020
setdiscovery: avoid a full changelog graph traversal
We were definitely being suboptimal here: we were constructing two full sets,
one with the full set of common nodes (i.e. a graph traversal) and one with all
nodes. Then we subtract one set from the other. This whole process is
O(commits) and causes discovery to be significantly slower than it should be.
Instead, keep track of common incrementally and keep undecided as small as
possible.
This makes discovery massively faster on large repos: on one such repo, 'hg
debugdiscovery' over SSH with one commit missing on the client and five on the
server went from 4.5 seconds to 1.5. (An 'hg debugdiscovery' with no commits
missing on the client, i.e. connection startup time, was 1.2 seconds.)
author | Siddharth Agarwal <sid0@fb.com> |
---|---|
date | Sun, 16 Nov 2014 00:40:29 -0800 |
parents | e34106fa0dc3 |
children | cd03fbd5ab57 |
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#!/usr/bin/env python # # Dumps output generated by Mercurial's command server in a formatted style to a # given file or stderr if '-' is specified. Output is also written in its raw # format to stdout. # # $ ./hg serve --cmds pipe | ./contrib/debugcmdserver.py - # o, 52 -> 'capabilities: getencoding runcommand\nencoding: UTF-8' import sys, struct if len(sys.argv) != 2: print 'usage: debugcmdserver.py FILE' sys.exit(1) outputfmt = '>cI' outputfmtsize = struct.calcsize(outputfmt) if sys.argv[1] == '-': log = sys.stderr else: log = open(sys.argv[1], 'a') def read(size): data = sys.stdin.read(size) if not data: raise EOFError sys.stdout.write(data) sys.stdout.flush() return data try: while True: header = read(outputfmtsize) channel, length = struct.unpack(outputfmt, header) log.write('%s, %-4d' % (channel, length)) if channel in 'IL': log.write(' -> waiting for input\n') else: data = read(length) log.write(' -> %r\n' % data) log.flush() except EOFError: pass finally: if log != sys.stderr: log.close()