Mercurial > hg
view tests/test-sparse-revlog.t @ 39494:e72130f58f5d
snapshot: consider all snapshots in the parents' chains
There are no reasons to only consider full snapshot as a possible base for an
intermediate snapshot. Now that the basic principles have been set, we can
start adding more levels of snapshots.
We now consider all snapshots in the parent's chains (full or intermediate).
This creates a chain of intermediate snapshots, each smaller than the previous
one.
# Effect On The Test Repository
In the test repository, we can see a decrease in the revlog size and slightly
shorter delta chain.
However, that approach creates snapshots more frequently, increasing the risk
of ending into problematic cases in very branchy repositories (not triggered
by the test repository). The next changesets will remove that risk by adding
logic that increases deltas reuse.
author | Boris Feld <boris.feld@octobus.net> |
---|---|
date | Fri, 07 Sep 2018 11:17:30 -0400 |
parents | 3ca144f1c8dd |
children | 6a53842727c1 |
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==================================== Test delta choice with sparse revlog ==================================== Sparse-revlog usually shows the most gain on Manifest. However, it is simpler to general an appropriate file, so we test with a single file instead. The goal is to observe intermediate snapshot being created. We need a large enough file. Part of the content needs to be replaced repeatedly while some of it changes rarely. $ bundlepath="$TESTDIR/artifacts/cache/big-file-churn.hg" $ expectedhash=`cat "$bundlepath".md5` $ if [ ! -f "$bundlepath" ]; then > echo 'skipped: missing artifact, run "'"$TESTDIR"'/artifacts/scripts/generate-churning-bundle.py"' > exit 80 > fi $ currenthash=`f -M "$bundlepath" | cut -d = -f 2` $ if [ "$currenthash" != "$expectedhash" ]; then > echo 'skipped: outdated artifact, md5 "'"$currenthash"'" expected "'"$expectedhash"'" run "'"$TESTDIR"'/artifacts/scripts/generate-churning-bundle.py"' > exit 80 > fi $ cat >> $HGRCPATH << EOF > [format] > sparse-revlog = yes > [storage] > revlog.optimize-delta-parent-choice = yes > EOF $ hg init sparse-repo $ cd sparse-repo $ hg unbundle $bundlepath adding changesets adding manifests adding file changes added 5001 changesets with 5001 changes to 1 files (+89 heads) new changesets 9706f5af64f4:d9032adc8114 (5001 drafts) (run 'hg heads' to see heads, 'hg merge' to merge) $ hg up 1 files updated, 0 files merged, 0 files removed, 0 files unresolved updated to "d9032adc8114: commit #5000" 89 other heads for branch "default" $ hg log --stat -r 0:3 changeset: 0:9706f5af64f4 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: initial commit SPARSE-REVLOG-TEST-FILE | 10500 ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 10500 insertions(+), 0 deletions(-) changeset: 1:724907deaa5e user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: commit #1 SPARSE-REVLOG-TEST-FILE | 1068 +++++++++++++++++++++++----------------------- 1 files changed, 534 insertions(+), 534 deletions(-) changeset: 2:62c41bce3e5d user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: commit #2 SPARSE-REVLOG-TEST-FILE | 1068 +++++++++++++++++++++++----------------------- 1 files changed, 534 insertions(+), 534 deletions(-) changeset: 3:348a9cbd6959 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: commit #3 SPARSE-REVLOG-TEST-FILE | 1068 +++++++++++++++++++++++----------------------- 1 files changed, 534 insertions(+), 534 deletions(-) $ f -s .hg/store/data/*.d .hg/store/data/_s_p_a_r_s_e-_r_e_v_l_o_g-_t_e_s_t-_f_i_l_e.d: size=63812493 $ hg debugrevlog * format : 1 flags : generaldelta revisions : 5001 merges : 625 (12.50%) normal : 4376 (87.50%) revisions : 5001 empty : 0 ( 0.00%) text : 0 (100.00%) delta : 0 (100.00%) snapshot : 179 ( 3.58%) lvl-0 : 4 ( 0.08%) lvl-1 : 49 ( 0.98%) lvl-2 : 56 ( 1.12%) lvl-3 : 63 ( 1.26%) lvl-4 : 7 ( 0.14%) deltas : 4822 (96.42%) revision size : 63812493 snapshot : 10745878 (16.84%) lvl-0 : 804204 ( 1.26%) lvl-1 : 4986508 ( 7.81%) lvl-2 : 2858810 ( 4.48%) lvl-3 : 1958906 ( 3.07%) lvl-4 : 137450 ( 0.22%) deltas : 53066615 (83.16%) chunks : 5001 0x78 (x) : 5001 (100.00%) chunks size : 63812493 0x78 (x) : 63812493 (100.00%) avg chain length : 17 max chain length : 45 max chain reach : 27506743 compression ratio : 27 uncompressed data size (min/max/avg) : 346468 / 346472 / 346471 full revision size (min/max/avg) : 201007 / 201077 / 201051 inter-snapshot size (min/max/avg) : 13223 / 172097 / 56809 level-1 (min/max/avg) : 13223 / 172097 / 101765 level-2 (min/max/avg) : 28558 / 85237 / 51050 level-3 (min/max/avg) : 14647 / 41752 / 31093 level-4 (min/max/avg) : 18596 / 20760 / 19635 delta size (min/max/avg) : 10649 / 104791 / 11005 deltas against prev : 4171 (86.50%) where prev = p1 : 4127 (98.95%) where prev = p2 : 0 ( 0.00%) other : 44 ( 1.05%) deltas against p1 : 633 (13.13%) deltas against p2 : 18 ( 0.37%) deltas against other : 0 ( 0.00%)