Mercurial > hg
view tests/test-narrow-clone-no-ellipsis.t @ 39492:a33f394b2bfd
snapshot: try intermediate snapshot against parents' base
# Regarding The Series Started By This Changeset
This is the first changesets of a group adjusting delta chain strategy to
build a useful chain of intermediate snapshots. The series will introduce a
full strategy to produce chains of multiple snapshots on top of which a
"usual" delta chain will be built.
That strategy will have multiple steps to maximize snapshot reuse, avoiding
pathological cases and improving overall compression in very branchy
repositories. An important property of sparse-revlog using such snapshot-chain
is that they can use very short delta chain without problematic impact on the
resulting compression. Shorter delta chains are important to achieve good
performance.
To make each step clear, we'll introduce them one by one.
See the end of this series for full details.
# Regarding This Changeset
Before this change, if we cannot store the current revision as a delta against
a "simple" candidate (p1, p2, prev), we created a new level-0 snapshot (also
called full snapshot).
As the first step, we introduce a simple strategy: try an intermediate level-1
snapshot against the chain base of the "current revision" parents.
The "current revision" is the one we are currently trying to store in the
revlog, triggering this search for a good delta base.
The first item in the chain is always a level-0 snapshot.
# Effect On The Test Repository
We can already see the effect on the test-repository. Most of the snapshots
have shifted from level 0 to level 1. The overall size has slightly decreased.
(However, keep in mind that this repository only emulates real data)
# Regarding Statistic
The current series focuses on improving the chain built. Improving the
performance of this logic will be done as a second step. Sparse-revlog is
still experimental and disabled by default.
We'll provide more statistic about resulting size and delta chain at the end
of this series.
author | Boris Feld <boris.feld@octobus.net> |
---|---|
date | Fri, 07 Sep 2018 11:17:29 -0400 |
parents | f4d4bd8c8911 |
children | 8301741e1f89 |
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$ . "$TESTDIR/narrow-library.sh" $ hg init master $ cd master $ mkdir dir $ mkdir dir/src $ cd dir/src $ for x in `$TESTDIR/seq.py 20`; do echo $x > "f$x"; hg add "f$x"; hg commit -m "Commit src $x"; done $ cd .. $ mkdir tests $ cd tests $ for x in `$TESTDIR/seq.py 20`; do echo $x > "t$x"; hg add "t$x"; hg commit -m "Commit test $x"; done $ cd ../../.. narrow clone a file, f10 $ hg clone --narrow ssh://user@dummy/master narrow --noupdate --include "dir/src/f10" requesting all changes adding changesets adding manifests adding file changes added 40 changesets with 1 changes to 1 files new changesets *:* (glob) $ cd narrow $ cat .hg/requires | grep -v generaldelta dotencode fncache narrowhg-experimental revlogv1 store testonly-simplestore (reposimplestore !) $ hg tracked I path:dir/src/f10 $ hg update 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/src dir/src/f10 $ cat dir/src/f10 10 $ cd .. narrow clone a directory, tests/, except tests/t19 $ hg clone --narrow ssh://user@dummy/master narrowdir --noupdate --include "dir/tests/" --exclude "dir/tests/t19" requesting all changes adding changesets adding manifests adding file changes added 40 changesets with 19 changes to 19 files new changesets *:* (glob) $ cd narrowdir $ hg tracked I path:dir/tests X path:dir/tests/t19 $ hg update 19 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/tests dir/tests/t1 dir/tests/t10 dir/tests/t11 dir/tests/t12 dir/tests/t13 dir/tests/t14 dir/tests/t15 dir/tests/t16 dir/tests/t17 dir/tests/t18 dir/tests/t2 dir/tests/t20 dir/tests/t3 dir/tests/t4 dir/tests/t5 dir/tests/t6 dir/tests/t7 dir/tests/t8 dir/tests/t9 $ cd .. narrow clone everything but a directory (tests/) $ hg clone --narrow ssh://user@dummy/master narrowroot --noupdate --exclude "dir/tests" requesting all changes adding changesets adding manifests adding file changes added 40 changesets with 20 changes to 20 files new changesets *:* (glob) $ cd narrowroot $ hg tracked I path:. X path:dir/tests $ hg update 20 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/src dir/src/f1 dir/src/f10 dir/src/f11 dir/src/f12 dir/src/f13 dir/src/f14 dir/src/f15 dir/src/f16 dir/src/f17 dir/src/f18 dir/src/f19 dir/src/f2 dir/src/f20 dir/src/f3 dir/src/f4 dir/src/f5 dir/src/f6 dir/src/f7 dir/src/f8 dir/src/f9 $ cd .. Testing the --narrowspec flag to clone $ cat >> narrowspecs <<EOF > %include foo > [include] > path:dir/tests/ > file:dir/src/f12 > EOF $ hg clone ssh://user@dummy/master specfile --narrowspec narrowspecs reading narrowspec from '$TESTTMP/narrowspecs' abort: cannot specify other files using '%include' in narrowspec [255] $ cat > narrowspecs <<EOF > [include] > path:dir/tests/ > file:dir/src/f12 > EOF $ hg clone ssh://user@dummy/master specfile --narrowspec narrowspecs reading narrowspec from '$TESTTMP/narrowspecs' requesting all changes adding changesets adding manifests adding file changes added 40 changesets with 20 changes to 20 files new changesets 681085829a73:26ce255d5b5d updating to branch default 20 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd specfile $ hg tracked I path:dir/tests I path:file:dir/src/f12 $ cd ..