Mercurial > hg
view tests/test-custom-filters.t @ 39560:84bf6ded9317
wireprotoframing: buffer emitted data to reduce frame count
An upcoming commit introduces a wire protocol command that can emit
hundreds of thousands of small objects. Without a buffering layer,
we would emit a single, small frame for every object. Performance
profiling revealed this to be a source of significant overhead for
both client and server.
This commit introduces a very crude buffering layer so that we emit
fewer, bigger frames in such a scenario. This code will likely get
rewritten in the future to be part of the streams API, as we'll
need a similar strategy for compressing data. I don't want to think
about it too much at the moment though.
server
before: user 32.500+0.000 sys 1.160+0.000
after: user 20.230+0.010 sys 0.180+0.000
client
before: user 133.400+0.000 sys 93.120+0.000
after: user 68.370+0.000 sys 32.950+0.000
This appears to indicate we have significant overhead in the frame
processing code on both client and server. It might be worth profiling
that at some point...
Differential Revision: https://phab.mercurial-scm.org/D4473
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 29 Aug 2018 16:43:17 -0700 |
parents | 6e713711331b |
children | ee9981bc8b44 |
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$ hg init $ cat > .hg/hgrc <<EOF > [extensions] > prefixfilter = prefix.py > [encode] > *.txt = stripprefix: Copyright 2046, The Masters > [decode] > *.txt = insertprefix: Copyright 2046, The Masters > EOF $ cat > prefix.py <<EOF > from mercurial import error > def stripprefix(s, cmd, filename, **kwargs): > header = b'%s\n' % cmd > if s[:len(header)] != header: > raise error.Abort(b'missing header "%s" in %s' % (cmd, filename)) > return s[len(header):] > def insertprefix(s, cmd): > return b'%s\n%s' % (cmd, s) > def reposetup(ui, repo): > repo.adddatafilter(b'stripprefix:', stripprefix) > repo.adddatafilter(b'insertprefix:', insertprefix) > EOF $ cat > .hgignore <<EOF > .hgignore > prefix.py > prefix.pyc > EOF $ cat > stuff.txt <<EOF > Copyright 2046, The Masters > Some stuff to ponder very carefully. > EOF $ hg add stuff.txt $ hg ci -m stuff Repository data: $ hg cat stuff.txt Some stuff to ponder very carefully. Fresh checkout: $ rm stuff.txt $ hg up -C 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cat stuff.txt Copyright 2046, The Masters Some stuff to ponder very carefully. $ echo "Very very carefully." >> stuff.txt $ hg stat M stuff.txt $ echo "Unauthorized material subject to destruction." > morestuff.txt Problem encoding: $ hg add morestuff.txt $ hg ci -m morestuff abort: missing header "Copyright 2046, The Masters" in morestuff.txt [255] $ hg stat M stuff.txt A morestuff.txt