Mercurial > hg
view tests/test-convert-p4.t @ 38893:23d582caae30
changegroup: capture revision delta in a data structure
The current changegroup generation code is tightly coupled to
the revlog API. This tight coupling makes it difficult to implement
alternate storage backends without requiring a large surface area
of the revlog API to be exposed. This is not desirable.
In order to support changegroup generation with non-revlog storage,
we'll need to abstract the concept of delta generation.
This commit is the first step down that road. We introduce a
data structure for representing a delta in a changegroup.
The API still leaves a lot to be desired. But at least we now
have separation between data and actions performed on it.
As part of this, we tweak behavior slightly: we no longer
concatenate the delta prefix with the metadata header. Instead,
we track and emit the prefix as a separate chunk. This shouldn't
have any meaningful impact since all the chunks just get sent to
the wire, the compressor, etc.
Because we're introducing a new object, this does add some
overhead to changegroup execution. `hg perfchangegroupchangelog`
on my clone of the Mercurial repo (~40,000 visible revisions in
the changelog) slows down a bit:
! wall 1.268600 comb 1.270000 user 1.270000 sys 0.000000 (best of 8)
! wall 1.419479 comb 1.410000 user 1.410000 sys 0.000000 (best of 8)
With for `hg bundle -t none-v2 -a /dev/null`:
before: real 6.610 secs (user 6.460+0.000 sys 0.140+0.000)
after: real 7.210 secs (user 7.060+0.000 sys 0.140+0.000)
I plan to claw back this regression in future commits. And I may
even do away with this data structure once the refactor is complete.
For now, it makes things easier to comprehend.
Differential Revision: https://phab.mercurial-scm.org/D4075
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 03 Aug 2018 10:05:26 -0700 |
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