Mercurial > hg
view tests/test-push-validation.t @ 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 | f2719b387380 |
children | f009804e2a43 |
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$ hg init test $ cd test $ cat > .hg/hgrc <<EOF > [server] > validate=1 > EOF $ echo alpha > alpha $ echo beta > beta $ hg addr adding alpha adding beta $ hg ci -m 1 $ cd .. $ hg clone test test-clone updating to branch default 2 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd test-clone $ cp .hg/store/data/beta.i tmp $ echo blah >> beta $ hg ci -m '2 (corrupt)' $ mv tmp .hg/store/data/beta.i Expected to fail: $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files beta@1: dddc47b3ba30 in manifests not found 2 files, 2 changesets, 2 total revisions 1 integrity errors encountered! (first damaged changeset appears to be 1) [1] Expected to fail: $ hg push pushing to $TESTTMP/test (glob) searching for changes adding changesets adding manifests adding file changes transaction abort! rollback completed abort: missing file data for beta:dddc47b3ba30e54484720ce0f4f768a0f4b6efb9 - run hg verify [255] $ cd ..