Mercurial > hg
view mercurial/hook.py @ 17970:0b03454abae7
ancestor: faster algorithm for difference of ancestor sets
One of the major reasons rebase is slow in large repositories is
the computation of the detach set: the set of ancestors of the
changesets to rebase not in the destination parent. This is currently
done via a revset that does two walks all the way to the root of
the DAG. Instead of doing that, to find ancestors of a set <revs>
not in another set <common> we walk up the tree in reverse revision
number order, maintaining sets of nodes visited from <revs>, <common>
or both.
For the common case where the sets are close both topologically and
in revision number (relative to repository size), this has been
found to speed up rebase by around 15-20%. When the nodes are farther
apart and the DAG is highly branching, it is harder to say which
would win.
Here's how long computing the detach set takes in a linear repository
with over 400000 changesets, rebasing near tip:
Rebasing across 4 changesets
Revset method: 2.2s
New algorithm: 0.00015s
Rebasing across 250 changesets
Revset method: 2.2s
New algorithm: 0.00069s
Rebasing across 10000 changesets
Revset method: 2.4s
New algorithm: 0.019s
author | Siddharth Agarwal <sid0@fb.com> |
---|---|
date | Mon, 26 Nov 2012 11:46:51 -0800 |
parents | 72803c8edaa4 |
children | 6180dcb29ec5 |
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# hook.py - hook support for mercurial # # Copyright 2007 Matt Mackall <mpm@selenic.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 i18n import _ import os, sys import extensions, util def _pythonhook(ui, repo, name, hname, funcname, args, throw): '''call python hook. hook is callable object, looked up as name in python module. if callable returns "true", hook fails, else passes. if hook raises exception, treated as hook failure. exception propagates if throw is "true". reason for "true" meaning "hook failed" is so that unmodified commands (e.g. mercurial.commands.update) can be run as hooks without wrappers to convert return values.''' ui.note(_("calling hook %s: %s\n") % (hname, funcname)) obj = funcname if not util.safehasattr(obj, '__call__'): d = funcname.rfind('.') if d == -1: raise util.Abort(_('%s hook is invalid ("%s" not in ' 'a module)') % (hname, funcname)) modname = funcname[:d] oldpaths = sys.path if util.mainfrozen(): # binary installs require sys.path manipulation modpath, modfile = os.path.split(modname) if modpath and modfile: sys.path = sys.path[:] + [modpath] modname = modfile try: obj = __import__(modname) except ImportError: e1 = sys.exc_type, sys.exc_value, sys.exc_traceback try: # extensions are loaded with hgext_ prefix obj = __import__("hgext_%s" % modname) except ImportError: e2 = sys.exc_type, sys.exc_value, sys.exc_traceback if ui.tracebackflag: ui.warn(_('exception from first failed import attempt:\n')) ui.traceback(e1) if ui.tracebackflag: ui.warn(_('exception from second failed import attempt:\n')) ui.traceback(e2) raise util.Abort(_('%s hook is invalid ' '(import of "%s" failed)') % (hname, modname)) sys.path = oldpaths try: for p in funcname.split('.')[1:]: obj = getattr(obj, p) except AttributeError: raise util.Abort(_('%s hook is invalid ' '("%s" is not defined)') % (hname, funcname)) if not util.safehasattr(obj, '__call__'): raise util.Abort(_('%s hook is invalid ' '("%s" is not callable)') % (hname, funcname)) try: try: # redirect IO descriptors to the ui descriptors so hooks # that write directly to these don't mess up the command # protocol when running through the command server old = sys.stdout, sys.stderr, sys.stdin sys.stdout, sys.stderr, sys.stdin = ui.fout, ui.ferr, ui.fin r = obj(ui=ui, repo=repo, hooktype=name, **args) except KeyboardInterrupt: raise except Exception, exc: if isinstance(exc, util.Abort): ui.warn(_('error: %s hook failed: %s\n') % (hname, exc.args[0])) else: ui.warn(_('error: %s hook raised an exception: ' '%s\n') % (hname, exc)) if throw: raise ui.traceback() return True finally: sys.stdout, sys.stderr, sys.stdin = old if r: if throw: raise util.Abort(_('%s hook failed') % hname) ui.warn(_('warning: %s hook failed\n') % hname) return r def _exthook(ui, repo, name, cmd, args, throw): ui.note(_("running hook %s: %s\n") % (name, cmd)) env = {} for k, v in args.iteritems(): if util.safehasattr(v, '__call__'): v = v() if isinstance(v, dict): # make the dictionary element order stable across Python # implementations v = ('{' + ', '.join('%r: %r' % i for i in sorted(v.iteritems())) + '}') env['HG_' + k.upper()] = v if repo: cwd = repo.root else: cwd = os.getcwd() if 'HG_URL' in env and env['HG_URL'].startswith('remote:http'): r = util.system(cmd, environ=env, cwd=cwd, out=ui) else: r = util.system(cmd, environ=env, cwd=cwd, out=ui.fout) if r: desc, r = util.explainexit(r) if throw: raise util.Abort(_('%s hook %s') % (name, desc)) ui.warn(_('warning: %s hook %s\n') % (name, desc)) return r def _allhooks(ui): hooks = [] for name, cmd in ui.configitems('hooks'): if not name.startswith('priority'): priority = ui.configint('hooks', 'priority.%s' % name, 0) hooks.append((-priority, len(hooks), name, cmd)) return [(k, v) for p, o, k, v in sorted(hooks)] _redirect = False def redirect(state): global _redirect _redirect = state def hook(ui, repo, name, throw=False, **args): if not ui.callhooks: return False r = False oldstdout = -1 if _redirect: try: stdoutno = sys.__stdout__.fileno() stderrno = sys.__stderr__.fileno() # temporarily redirect stdout to stderr, if possible if stdoutno >= 0 and stderrno >= 0: sys.__stdout__.flush() oldstdout = os.dup(stdoutno) os.dup2(stderrno, stdoutno) except AttributeError: # __stdout__/__stderr__ doesn't have fileno(), it's not a real file pass try: for hname, cmd in _allhooks(ui): if hname.split('.')[0] != name or not cmd: continue if util.safehasattr(cmd, '__call__'): r = _pythonhook(ui, repo, name, hname, cmd, args, throw) or r elif cmd.startswith('python:'): if cmd.count(':') >= 2: path, cmd = cmd[7:].rsplit(':', 1) path = util.expandpath(path) if repo: path = os.path.join(repo.root, path) try: mod = extensions.loadpath(path, 'hghook.%s' % hname) except Exception: ui.write(_("loading %s hook failed:\n") % hname) raise hookfn = getattr(mod, cmd) else: hookfn = cmd[7:].strip() r = _pythonhook(ui, repo, name, hname, hookfn, args, throw) or r else: r = _exthook(ui, repo, hname, cmd, args, throw) or r finally: if _redirect and oldstdout >= 0: os.dup2(oldstdout, stdoutno) os.close(oldstdout) return r