Mercurial > hg
view mercurial/sshserver.py @ 26945:8a256cee72c8 stable
tags: create new sortdict for performance reasons
sortdict internally maintains a list of keys in insertion order. When a
key is replaced via __setitem__, we .remove() from this list. This
involves a linear scan and array adjustment. This is an expensive
operation.
The tags reading code was calling into sortdict.__setitem__ for each tag
in a read .hgtags revision. For repositories with thousands of tags or
thousands of .hgtags revisions, the overhead from list.remove()
noticeable.
This patch creates a new sortdict() so __setitem__ calls don't incur a
list.remove.
This doesn't appear to have any performance impact on my Firefox
repository. But that's only because tags reading doesn't show up in
profiles to begin with. I'm still waiting to hear from a user with over
10,000 tags and hundreds of heads on the impact of this patch.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 12 Nov 2015 13:16:04 -0800 |
parents | 56b2bcea2529 |
children | 98e8313dcd9e |
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# sshserver.py - ssh protocol server support for mercurial # # Copyright 2005-2007 Matt Mackall <mpm@selenic.com> # Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import os import sys from . import ( error, hook, util, wireproto, ) class sshserver(wireproto.abstractserverproto): def __init__(self, ui, repo): self.ui = ui self.repo = repo self.lock = None self.fin = ui.fin self.fout = ui.fout hook.redirect(True) ui.fout = repo.ui.fout = ui.ferr # Prevent insertion/deletion of CRs util.setbinary(self.fin) util.setbinary(self.fout) def getargs(self, args): data = {} keys = args.split() for n in xrange(len(keys)): argline = self.fin.readline()[:-1] arg, l = argline.split() if arg not in keys: raise error.Abort("unexpected parameter %r" % arg) if arg == '*': star = {} for k in xrange(int(l)): argline = self.fin.readline()[:-1] arg, l = argline.split() val = self.fin.read(int(l)) star[arg] = val data['*'] = star else: val = self.fin.read(int(l)) data[arg] = val return [data[k] for k in keys] def getarg(self, name): return self.getargs(name)[0] def getfile(self, fpout): self.sendresponse('') count = int(self.fin.readline()) while count: fpout.write(self.fin.read(count)) count = int(self.fin.readline()) def redirect(self): pass def groupchunks(self, changegroup): while True: d = changegroup.read(4096) if not d: break yield d def sendresponse(self, v): self.fout.write("%d\n" % len(v)) self.fout.write(v) self.fout.flush() def sendstream(self, source): write = self.fout.write for chunk in source.gen: write(chunk) self.fout.flush() def sendpushresponse(self, rsp): self.sendresponse('') self.sendresponse(str(rsp.res)) def sendpusherror(self, rsp): self.sendresponse(rsp.res) def sendooberror(self, rsp): self.ui.ferr.write('%s\n-\n' % rsp.message) self.ui.ferr.flush() self.fout.write('\n') self.fout.flush() def serve_forever(self): try: while self.serve_one(): pass finally: if self.lock is not None: self.lock.release() sys.exit(0) handlers = { str: sendresponse, wireproto.streamres: sendstream, wireproto.pushres: sendpushresponse, wireproto.pusherr: sendpusherror, wireproto.ooberror: sendooberror, } def serve_one(self): cmd = self.fin.readline()[:-1] if cmd and cmd in wireproto.commands: rsp = wireproto.dispatch(self.repo, self, cmd) self.handlers[rsp.__class__](self, rsp) elif cmd: impl = getattr(self, 'do_' + cmd, None) if impl: r = impl() if r is not None: self.sendresponse(r) else: self.sendresponse("") return cmd != '' def _client(self): client = os.environ.get('SSH_CLIENT', '').split(' ', 1)[0] return 'remote:ssh:' + client