Mercurial > hg
view mercurial/repair.py @ 18063:34a1a639d835
revset.children: ignore rev numbers that are too low
This replaces unnecessary parentrevs() calls with calculating min(parentset).
Even though the min operation is O(size of parentset), since parentrevs is
relatively expensive, this tradeoff almost always works in our favour. In a
repository with over 400,000 changesets, hg perfrevset "children(X)" takes:
Set X Before After
-1 0.51s 0.06s
-1000: 0.55s 0.08s
-10000: 0.56s 0.10s
-100000: 0.60s 0.25s
-100000:-99000 0.55s 0.19s
0:100000 0.60s 0.61s
all() 0.72s 0.74s
The relative performance is similar for Mercurial's own repository -- several
times faster in most cases, slightly slower for revisions close to 0 and
all().
author | Siddharth Agarwal <sid0@fb.com> |
---|---|
date | Fri, 07 Dec 2012 10:37:43 -0800 |
parents | fe8caf28d580 |
children | f8a13f061a8a |
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# repair.py - functions for repository repair for mercurial # # Copyright 2005, 2006 Chris Mason <mason@suse.com> # Copyright 2007 Matt Mackall # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from mercurial import changegroup from mercurial.node import short from mercurial.i18n import _ import os import errno def _bundle(repo, bases, heads, node, suffix, compress=True): """create a bundle with the specified revisions as a backup""" cg = repo.changegroupsubset(bases, heads, 'strip') backupdir = repo.join("strip-backup") if not os.path.isdir(backupdir): os.mkdir(backupdir) name = os.path.join(backupdir, "%s-%s.hg" % (short(node), suffix)) if compress: bundletype = "HG10BZ" else: bundletype = "HG10UN" return changegroup.writebundle(cg, name, bundletype) def _collectfiles(repo, striprev): """find out the filelogs affected by the strip""" files = set() for x in xrange(striprev, len(repo)): files.update(repo[x].files()) return sorted(files) def _collectbrokencsets(repo, files, striprev): """return the changesets which will be broken by the truncation""" s = set() def collectone(revlog): linkgen = (revlog.linkrev(i) for i in revlog) # find the truncation point of the revlog for lrev in linkgen: if lrev >= striprev: break # see if any revision after this point has a linkrev # less than striprev (those will be broken by strip) for lrev in linkgen: if lrev < striprev: s.add(lrev) collectone(repo.manifest) for fname in files: collectone(repo.file(fname)) return s def strip(ui, repo, nodelist, backup="all", topic='backup'): repo = repo.unfiltered() # It simplifies the logic around updating the branchheads cache if we only # have to consider the effect of the stripped revisions and not revisions # missing because the cache is out-of-date. repo.updatebranchcache() cl = repo.changelog # TODO handle undo of merge sets if isinstance(nodelist, str): nodelist = [nodelist] striplist = [cl.rev(node) for node in nodelist] striprev = min(striplist) # Generate set of branches who will have nodes stripped. striprevs = repo.revs("%ld::", striplist) stripbranches = set([repo[rev].branch() for rev in striprevs]) # Set of potential new heads resulting from the strip. The parents of any # node removed could be a new head because the node to be removed could have # been the only child of the parent. newheadrevs = repo.revs("parents(%ld::) - %ld::", striprevs, striprevs) newheadnodes = set([cl.node(rev) for rev in newheadrevs]) newheadbranches = set([repo[rev].branch() for rev in newheadrevs]) keeppartialbundle = backup == 'strip' # Some revisions with rev > striprev may not be descendants of striprev. # We have to find these revisions and put them in a bundle, so that # we can restore them after the truncations. # To create the bundle we use repo.changegroupsubset which requires # the list of heads and bases of the set of interesting revisions. # (head = revision in the set that has no descendant in the set; # base = revision in the set that has no ancestor in the set) tostrip = set(striplist) for rev in striplist: for desc in cl.descendants([rev]): tostrip.add(desc) files = _collectfiles(repo, striprev) saverevs = _collectbrokencsets(repo, files, striprev) # compute heads saveheads = set(saverevs) for r in xrange(striprev + 1, len(cl)): if r not in tostrip: saverevs.add(r) saveheads.difference_update(cl.parentrevs(r)) saveheads.add(r) saveheads = [cl.node(r) for r in saveheads] # compute base nodes if saverevs: descendants = set(cl.descendants(saverevs)) saverevs.difference_update(descendants) savebases = [cl.node(r) for r in saverevs] stripbases = [cl.node(r) for r in tostrip] # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), but # is much faster newbmtarget = repo.revs('max(parents(%ld) - (%ld))', tostrip, tostrip) if newbmtarget: newbmtarget = repo[newbmtarget[0]].node() else: newbmtarget = '.' bm = repo._bookmarks updatebm = [] for m in bm: rev = repo[bm[m]].rev() if rev in tostrip: updatebm.append(m) # create a changegroup for all the branches we need to keep backupfile = None if backup == "all": backupfile = _bundle(repo, stripbases, cl.heads(), node, topic) repo.ui.status(_("saved backup bundle to %s\n") % backupfile) if saveheads or savebases: # do not compress partial bundle if we remove it from disk later chgrpfile = _bundle(repo, savebases, saveheads, node, 'temp', compress=keeppartialbundle) mfst = repo.manifest tr = repo.transaction("strip") offset = len(tr.entries) try: tr.startgroup() cl.strip(striprev, tr) mfst.strip(striprev, tr) for fn in files: repo.file(fn).strip(striprev, tr) tr.endgroup() try: for i in xrange(offset, len(tr.entries)): file, troffset, ignore = tr.entries[i] repo.sopener(file, 'a').truncate(troffset) tr.close() except: # re-raises tr.abort() raise if saveheads or savebases: ui.note(_("adding branch\n")) f = open(chgrpfile, "rb") gen = changegroup.readbundle(f, chgrpfile) if not repo.ui.verbose: # silence internal shuffling chatter repo.ui.pushbuffer() repo.addchangegroup(gen, 'strip', 'bundle:' + chgrpfile, True) if not repo.ui.verbose: repo.ui.popbuffer() f.close() if not keeppartialbundle: os.unlink(chgrpfile) # remove undo files for undofile in repo.undofiles(): try: os.unlink(undofile) except OSError, e: if e.errno != errno.ENOENT: ui.warn(_('error removing %s: %s\n') % (undofile, str(e))) for m in updatebm: bm[m] = repo[newbmtarget].node() bm.write() except: # re-raises if backupfile: ui.warn(_("strip failed, full bundle stored in '%s'\n") % backupfile) elif saveheads: ui.warn(_("strip failed, partial bundle stored in '%s'\n") % chgrpfile) raise if len(stripbranches) == 1 and len(newheadbranches) == 1 \ and stripbranches == newheadbranches: repo.destroyed(newheadnodes) else: # Multiple branches involved in strip. Will allow branchcache to become # invalid and later on rebuilt from scratch repo.destroyed()