Mercurial > hg
view tests/test-bundle2-pushback.t @ 42743:8c9a6adec67a
rust-discovery: using the children cache in add_missing
The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.
The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.
This is a case where staying on the same side of the interface
between the two languages has clear benefits.
On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.
For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:
Rust version with simple iteration
addcommons: 57.287us
first undecided computation: 184.278334ms
first children cache computation: 131.056us
addmissings iteration: 42.766us
first addinfo total: 185.24 ms
Python + C version
first addcommons: 0.29 ms
addcommons 0.21 ms
first undecided computation 191.35 ms
addmissings 45.75 ms
first addinfo total: 237.77 ms
On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:
Rust version:
first undecided computation: 293.842629ms
first children cache computation: 407.911297ms
addmissings iteration: 34.312869ms
first addinfo total: 776.02 ms
taking initial sample
query 2: sampling time: 1318.38 ms
query 2; still undecided: 1005013, sample size is: 200
addmissings: 143.062us
Python + C version:
first undecided computation 298.13 ms
addmissings 80.13 ms
first addinfo total: 399.62 ms
taking initial sample
query 2: sampling time: 3957.23 ms
query 2; still undecided: 1005013, sample size is: 200
addmissings 52.88 ms
Differential Revision: https://phab.mercurial-scm.org/D6428
author | Georges Racinet <georges.racinet@octobus.net> |
---|---|
date | Tue, 16 Apr 2019 01:16:39 +0200 |
parents | c70bdd222dcd |
children | 9c4204b7f3e4 |
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#testcases sshv1 sshv2 #if sshv2 $ cat >> $HGRCPATH << EOF > [experimental] > sshpeer.advertise-v2 = true > sshserver.support-v2 = true > EOF #endif $ cat > bundle2.py << EOF > """A small extension to test bundle2 pushback parts. > Current bundle2 implementation doesn't provide a way to generate those > parts, so they must be created by extensions. > """ > from __future__ import absolute_import > from mercurial import bundle2, exchange, pushkey, util > def _newhandlechangegroup(op, inpart): > """This function wraps the changegroup part handler for getbundle. > It issues an additional pushkey part to send a new > bookmark back to the client""" > result = bundle2.handlechangegroup(op, inpart) > if b'pushback' in op.reply.capabilities: > params = {b'namespace': b'bookmarks', > b'key': b'new-server-mark', > b'old': b'', > b'new': b'tip'} > encodedparams = [(k, pushkey.encode(v)) > for (k, v) in params.items()] > op.reply.newpart(b'pushkey', mandatoryparams=encodedparams) > else: > op.reply.newpart(b'output', data=b'pushback not enabled') > return result > _newhandlechangegroup.params = bundle2.handlechangegroup.params > bundle2.parthandlermapping[b'changegroup'] = _newhandlechangegroup > EOF $ cat >> $HGRCPATH <<EOF > [ui] > ssh = "$PYTHON" "$TESTDIR/dummyssh" > username = nobody <no.reply@example.com> > > [alias] > tglog = log -G -T "{desc} [{phase}:{node|short}]" > EOF Set up server repository $ hg init server $ cd server $ echo c0 > f0 $ hg commit -Am 0 adding f0 Set up client repository $ cd .. $ hg clone ssh://user@dummy/server client -q $ cd client Enable extension $ cat >> $HGRCPATH <<EOF > [extensions] > bundle2=$TESTTMP/bundle2.py > EOF Without config $ cd ../client $ echo c1 > f1 $ hg commit -Am 1 adding f1 $ hg push pushing to ssh://user@dummy/server searching for changes remote: adding changesets remote: adding manifests remote: adding file changes remote: added 1 changesets with 1 changes to 1 files remote: pushback not enabled $ hg bookmark no bookmarks set $ cd ../server $ hg tglog o 1 [public:2b9c7234e035] | @ 0 [public:6cee5c8f3e5b] With config $ cd ../client $ echo '[experimental]' >> .hg/hgrc $ echo 'bundle2.pushback = True' >> .hg/hgrc $ echo c2 > f2 $ hg commit -Am 2 adding f2 $ hg push pushing to ssh://user@dummy/server searching for changes remote: adding changesets remote: adding manifests remote: adding file changes remote: added 1 changesets with 1 changes to 1 files $ hg bookmark new-server-mark 2:0a76dfb2e179 $ cd ../server $ hg tglog o 2 [public:0a76dfb2e179] | o 1 [public:2b9c7234e035] | @ 0 [public:6cee5c8f3e5b]