Mercurial > hg
view mercurial/setdiscovery.py @ 23575:a2f139d25845
subrepo: drop the 'ui' parameter to archive()
The current state of subrepo methods is to pass a 'ui' object to some methods,
which has the effect of overriding the subrepo configuration since it is the
root repo's 'ui' that is passed along as deep as there are subrepos. Other
subrepo method are *not* passed the root 'ui', and instead delegate to their
repo object's 'ui'. Even in the former case where the root 'ui' is available,
some methods are inconsistent in their use of both the root 'ui' and the local
repo's 'ui'. (Consider hg._incoming() uses the root 'ui' for path expansion
and some status messages, but also calls bundlerepo.getremotechanges(), which
eventually calls discovery.findcommonincoming(), which calls
setdiscovery.findcommonheads(), which calls status() on the local repo 'ui'.)
This inconsistency with respect to the configured output level is probably
always hidden, because --verbose, --debug and --quiet, along with their 'ui.xxx'
equivalents in the global and user level hgrc files are propagated from the
parent repo to the subrepo via 'baseui'. The 'ui.xxx' settings in the parent
repo hgrc file are not propagated, but that seems like an unusual thing to set
on a per repo config file. Any 'ui.xxx' options changed by --config are also
not propagated, because they are set on repo.ui by dispatch.py, not repo.baseui.
The goal here is to cleanup the subrepo methods by dropping the 'ui' parameter,
which in turn prevents mixing subtly different 'ui' instances on a given subrepo
level. Some methods use more than just the output level settings in 'ui' (add
for example ends up calling scmutil.checkportabilityalert() with both the root
and local repo's 'ui' at different points). This series just goes for the low
hanging fruit and switches methods that only use the output level.
If we really care about not letting a subrepo config override the root repo's
output level, we can propagate the verbose, debug and quiet settings to the
subrepo in the same way 'ui.commitsubrepos' is in hgsubrepo.__init__.
Archive only uses the 'ui' object to call its progress() method, and gitsubrepo
calls status().
author | Matt Harbison <matt_harbison@yahoo.com> |
---|---|
date | Sat, 13 Dec 2014 14:53:46 -0500 |
parents | f8a2647fe020 |
children | 4ef2f2fa8b8b |
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# setdiscovery.py - improved discovery of common nodeset for mercurial # # Copyright 2010 Benoit Boissinot <bboissin@gmail.com> # and Peter Arrenbrecht <peter@arrenbrecht.ch> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """ Algorithm works in the following way. You have two repository: local and remote. They both contains a DAG of changelists. The goal of the discovery protocol is to find one set of node *common*, the set of nodes shared by local and remote. One of the issue with the original protocol was latency, it could potentially require lots of roundtrips to discover that the local repo was a subset of remote (which is a very common case, you usually have few changes compared to upstream, while upstream probably had lots of development). The new protocol only requires one interface for the remote repo: `known()`, which given a set of changelists tells you if they are present in the DAG. The algorithm then works as follow: - We will be using three sets, `common`, `missing`, `unknown`. Originally all nodes are in `unknown`. - Take a sample from `unknown`, call `remote.known(sample)` - For each node that remote knows, move it and all its ancestors to `common` - For each node that remote doesn't know, move it and all its descendants to `missing` - Iterate until `unknown` is empty There are a couple optimizations, first is instead of starting with a random sample of missing, start by sending all heads, in the case where the local repo is a subset, you computed the answer in one round trip. Then you can do something similar to the bisecting strategy used when finding faulty changesets. Instead of random samples, you can try picking nodes that will maximize the number of nodes that will be classified with it (since all ancestors or descendants will be marked as well). """ from node import nullid, nullrev from i18n import _ import random import util, dagutil def _updatesample(dag, nodes, sample, always, quicksamplesize=0): # if nodes is empty we scan the entire graph if nodes: heads = dag.headsetofconnecteds(nodes) else: heads = dag.heads() dist = {} visit = util.deque(heads) seen = set() factor = 1 while visit: curr = visit.popleft() if curr in seen: continue d = dist.setdefault(curr, 1) if d > factor: factor *= 2 if d == factor: if curr not in always: # need this check for the early exit below sample.add(curr) if quicksamplesize and (len(sample) >= quicksamplesize): return seen.add(curr) for p in dag.parents(curr): if not nodes or p in nodes: dist.setdefault(p, d + 1) visit.append(p) def _setupsample(dag, nodes, size): if len(nodes) <= size: return set(nodes), None, 0 always = dag.headsetofconnecteds(nodes) desiredlen = size - len(always) if desiredlen <= 0: # This could be bad if there are very many heads, all unknown to the # server. We're counting on long request support here. return always, None, desiredlen return always, set(), desiredlen def _takequicksample(dag, nodes, size, initial): always, sample, desiredlen = _setupsample(dag, nodes, size) if sample is None: return always if initial: fromset = None else: fromset = nodes _updatesample(dag, fromset, sample, always, quicksamplesize=desiredlen) sample.update(always) return sample def _takefullsample(dag, nodes, size): always, sample, desiredlen = _setupsample(dag, nodes, size) if sample is None: return always # update from heads _updatesample(dag, nodes, sample, always) # update from roots _updatesample(dag.inverse(), nodes, sample, always) assert sample sample = _limitsample(sample, desiredlen) if len(sample) < desiredlen: more = desiredlen - len(sample) sample.update(random.sample(list(nodes - sample - always), more)) sample.update(always) return sample def _limitsample(sample, desiredlen): """return a random subset of sample of at most desiredlen item""" if len(sample) > desiredlen: sample = set(random.sample(sample, desiredlen)) return sample def findcommonheads(ui, local, remote, initialsamplesize=100, fullsamplesize=200, abortwhenunrelated=True): '''Return a tuple (common, anyincoming, remoteheads) used to identify missing nodes from or in remote. ''' roundtrips = 0 cl = local.changelog dag = dagutil.revlogdag(cl) # early exit if we know all the specified remote heads already ui.debug("query 1; heads\n") roundtrips += 1 ownheads = dag.heads() sample = _limitsample(ownheads, initialsamplesize) # indices between sample and externalized version must match sample = list(sample) if remote.local(): # stopgap until we have a proper localpeer that supports batch() srvheadhashes = remote.heads() yesno = remote.known(dag.externalizeall(sample)) elif remote.capable('batch'): batch = remote.batch() srvheadhashesref = batch.heads() yesnoref = batch.known(dag.externalizeall(sample)) batch.submit() srvheadhashes = srvheadhashesref.value yesno = yesnoref.value else: # compatibility with pre-batch, but post-known remotes during 1.9 # development srvheadhashes = remote.heads() sample = [] if cl.tip() == nullid: if srvheadhashes != [nullid]: return [nullid], True, srvheadhashes return [nullid], False, [] # start actual discovery (we note this before the next "if" for # compatibility reasons) ui.status(_("searching for changes\n")) srvheads = dag.internalizeall(srvheadhashes, filterunknown=True) if len(srvheads) == len(srvheadhashes): ui.debug("all remote heads known locally\n") return (srvheadhashes, False, srvheadhashes,) if sample and len(ownheads) <= initialsamplesize and util.all(yesno): ui.note(_("all local heads known remotely\n")) ownheadhashes = dag.externalizeall(ownheads) return (ownheadhashes, True, srvheadhashes,) # full blown discovery # own nodes where I don't know if remote knows them undecided = dag.nodeset() # own nodes I know we both know # treat remote heads (and maybe own heads) as a first implicit sample # response common = cl.incrementalmissingrevs(srvheads) commoninsample = set(n for i, n in enumerate(sample) if yesno[i]) common.addbases(commoninsample) undecided = set(common.missingancestors(ownheads)) # own nodes I know remote lacks missing = set() full = False while undecided: if sample: missinginsample = [n for i, n in enumerate(sample) if not yesno[i]] missing.update(dag.descendantset(missinginsample, missing)) undecided.difference_update(missing) if not undecided: break if full: ui.note(_("sampling from both directions\n")) sample = _takefullsample(dag, undecided, size=fullsamplesize) targetsize = fullsamplesize elif common.hasbases(): # use cheapish initial sample ui.debug("taking initial sample\n") sample = _takefullsample(dag, undecided, size=fullsamplesize) targetsize = fullsamplesize else: # use even cheaper initial sample ui.debug("taking quick initial sample\n") sample = _takequicksample(dag, undecided, size=initialsamplesize, initial=True) targetsize = initialsamplesize sample = _limitsample(sample, targetsize) roundtrips += 1 ui.progress(_('searching'), roundtrips, unit=_('queries')) ui.debug("query %i; still undecided: %i, sample size is: %i\n" % (roundtrips, len(undecided), len(sample))) # indices between sample and externalized version must match sample = list(sample) yesno = remote.known(dag.externalizeall(sample)) full = True if sample: commoninsample = set(n for i, n in enumerate(sample) if yesno[i]) common.addbases(commoninsample) common.removeancestorsfrom(undecided) # heads(common) == heads(common.bases) since common represents common.bases # and all its ancestors result = dag.headsetofconnecteds(common.bases) # common.bases can include nullrev, but our contract requires us to not # return any heads in that case, so discard that result.discard(nullrev) ui.progress(_('searching'), None) ui.debug("%d total queries\n" % roundtrips) if not result and srvheadhashes != [nullid]: if abortwhenunrelated: raise util.Abort(_("repository is unrelated")) else: ui.warn(_("warning: repository is unrelated\n")) return (set([nullid]), True, srvheadhashes,) anyincoming = (srvheadhashes != [nullid]) return dag.externalizeall(result), anyincoming, srvheadhashes