Mercurial > hg
view tests/test-convert-p4.t @ 44363:f7459da77f23
nodemap: introduce an option to use mmap to read the nodemap mapping
The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.
This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).
Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:
Before:
* do not use the persistent nodemap
* use the CPython implementation of the index for nodemap
* use mmapping of the changelog index
After:
* use the MixedIndex Rust code, with the NodeTree object for nodemap access
(still in review)
* use the persistent nodemap data from disk
* access the persistent nodemap data through mmap
* use mmapping of the changelog index
The persistent nodemap greatly speed up most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.
Here are some numbers (in seconds) for the reference copy of mozilla-try:
Revset Before After abs-change speedup
-10000: 0.004622 0.005532 0.000910 × 0.83
-10: 0.000050 0.000132 0.000082 × 0.37
tip 0.000052 0.000085 0.000033 × 0.61
0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29
0 0.023521 0.000084 -0.023437 × 280.01
(-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37
(-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79
(-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55
:99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84
:9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68
:9 0.316450 0.000143 -0.316307 ×2212.93
On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.
Here are some numbers (in seconds) for the reference copy of mercurial:
Revset Before After abs-change speedup
-10: 0.000065 0.000097 0.000032 × 0.67
tip 0.000063 0.000078 0.000015 × 0.80
0 0.000561 0.000079 -0.000482 × 7.10
-10000: 0.004609 0.003648 -0.000961 × 1.26
0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35
(-10:) + :9 0.002187 0.000108 -0.002079 ×20.25
(-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68
(-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71
:9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96
:9 0.003854 0.000099 -0.003755 ×38.92
:99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02
Differential Revision: https://phab.mercurial-scm.org/D7894
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 11 Feb 2020 11:18:52 +0100 |
parents | 78ac8acfc4bd |
children |
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#require p4 $ echo "[extensions]" >> $HGRCPATH $ echo "convert = " >> $HGRCPATH create p4 depot $ P4ROOT=`pwd`/depot; export P4ROOT $ P4AUDIT=$P4ROOT/audit; export P4AUDIT $ P4JOURNAL=$P4ROOT/journal; export P4JOURNAL $ P4LOG=$P4ROOT/log; export P4LOG $ P4PORT=localhost:$HGPORT; export P4PORT $ P4DEBUG=1; export P4DEBUG start the p4 server $ [ ! -d $P4ROOT ] && mkdir $P4ROOT $ p4d -f -J off >$P4ROOT/stdout 2>$P4ROOT/stderr & $ echo $! >> $DAEMON_PIDS $ trap "echo stopping the p4 server ; p4 admin stop" EXIT $ # wait for the server to initialize $ while ! p4 ; do > sleep 1 > done >/dev/null 2>/dev/null create a client spec $ P4CLIENT=hg-p4-import; export P4CLIENT $ DEPOTPATH=//depot/test-mercurial-import/... $ p4 client -o | sed '/^View:/,$ d' >p4client $ echo View: >>p4client $ echo " $DEPOTPATH //$P4CLIENT/..." >>p4client $ p4 client -i <p4client Client hg-p4-import saved. populate the depot $ echo a > a $ mkdir b $ echo c > b/c $ p4 add a b/c //depot/test-mercurial-import/a#1 - opened for add //depot/test-mercurial-import/b/c#1 - opened for add $ p4 submit -d initial Submitting change 1. Locking 2 files ... add //depot/test-mercurial-import/a#1 add //depot/test-mercurial-import/b/c#1 Change 1 submitted. change some files $ p4 edit a //depot/test-mercurial-import/a#1 - opened for edit $ echo aa >> a $ p4 submit -d "change a" Submitting change 2. Locking 1 files ... edit //depot/test-mercurial-import/a#2 Change 2 submitted. $ p4 edit b/c //depot/test-mercurial-import/b/c#1 - opened for edit $ echo cc >> b/c $ p4 submit -d "change b/c" Submitting change 3. Locking 1 files ... edit //depot/test-mercurial-import/b/c#2 Change 3 submitted. convert $ hg convert -s p4 $DEPOTPATH dst initializing destination dst repository scanning source... reading p4 views collecting p4 changelists 1 initial 2 change a 3 change b/c sorting... converting... 2 initial 1 change a 0 change b/c $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n' rev=2 desc="change b/c" tags="tip" files="b/c" rev=1 desc="change a" tags="" files="a" rev=0 desc="initial" tags="" files="a b/c" change some files $ p4 edit a b/c //depot/test-mercurial-import/a#2 - opened for edit //depot/test-mercurial-import/b/c#2 - opened for edit $ echo aaa >> a $ echo ccc >> b/c $ p4 submit -d "change a b/c" Submitting change 4. Locking 2 files ... edit //depot/test-mercurial-import/a#3 edit //depot/test-mercurial-import/b/c#3 Change 4 submitted. convert again $ hg convert -s p4 $DEPOTPATH dst scanning source... reading p4 views collecting p4 changelists 4 change a b/c sorting... converting... 0 change a b/c $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n' rev=3 desc="change a b/c" tags="tip" files="a b/c" rev=2 desc="change b/c" tags="" files="b/c" rev=1 desc="change a" tags="" files="a" rev=0 desc="initial" tags="" files="a b/c" interesting names $ echo dddd > "d d" $ mkdir " e" $ echo fff >" e/ f" $ p4 add "d d" " e/ f" //depot/test-mercurial-import/d d#1 - opened for add //depot/test-mercurial-import/ e/ f#1 - opened for add $ p4 submit -d "add d e f" Submitting change 5. Locking 2 files ... add //depot/test-mercurial-import/ e/ f#1 add //depot/test-mercurial-import/d d#1 Change 5 submitted. convert again $ hg convert -s p4 $DEPOTPATH dst scanning source... reading p4 views collecting p4 changelists 5 add d e f sorting... converting... 0 add d e f $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n' rev=4 desc="add d e f" tags="tip" files=" e/ f d d" rev=3 desc="change a b/c" tags="" files="a b/c" rev=2 desc="change b/c" tags="" files="b/c" rev=1 desc="change a" tags="" files="a" rev=0 desc="initial" tags="" files="a b/c" empty commit message $ p4 edit a //depot/test-mercurial-import/a#3 - opened for edit $ echo aaaaa >> a $ p4 submit -d "" Submitting change 6. Locking 1 files ... edit //depot/test-mercurial-import/a#4 Change 6 submitted. $ hg convert -s p4 $DEPOTPATH dst scanning source... reading p4 views collecting p4 changelists 6 **empty changelist description** sorting... converting... 0 exit trap: stopping the p4 server