cborutil: change buffering strategy
Profiling revealed that we were spending a lot of time on the
line that was concatenating the old buffer with the incoming data
when attempting to decode long byte strings, such as manifest
revisions.
Essentially, we were feeding N chunks of size len(X) << len(Y) into
decode() and continuously allocating a new, larger buffer to hold
the undecoded input. This created substantial memory churn and
slowed down execution.
Changing the code to aggregate pending chunks in a list until we
have enough data to fully decode the next atom makes things much
more efficient.
I don't have exact data, but I recall the old code spending >1s
on manifest fulltexts from the mozilla-unified repo. The new code
doesn't significantly appear in profile output.
Differential Revision: https://phab.mercurial-scm.org/D4854
$ cat > loop.py <<EOF
> from __future__ import absolute_import
> import time
> from mercurial import commands, registrar
>
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> class incrementingtime(object):
> def __init__(self):
> self._time = 0.0
> def __call__(self):
> self._time += 0.25
> return self._time
> time.time = incrementingtime()
>
> @command(b'loop',
> [(b'', b'total', b'', b'override for total'),
> (b'', b'nested', False, b'show nested results'),
> (b'', b'parallel', False, b'show parallel sets of results')],
> b'hg loop LOOPS',
> norepo=True)
> def loop(ui, loops, **opts):
> loops = int(loops)
> total = None
> if loops >= 0:
> total = loops
> if opts.get('total', None):
> total = int(opts.get('total'))
> nested = False
> if opts.get('nested', None):
> nested = True
> loops = abs(loops)
>
> progress = ui.makeprogress(topiclabel, unit='loopnum', total=total)
> other = ui.makeprogress('other', unit='othernum', total=total)
> for i in range(loops):
> progress.update(i, item=getloopitem(i))
> if opts.get('parallel'):
> other.update(i, item='other.%d' % i)
> if nested:
> nested_steps = 2
> if i and i % 4 == 0:
> nested_steps = 5
> nested = ui.makeprogress('nested', unit='nestnum',
> total=nested_steps)
> for j in range(nested_steps):
> nested.update(j, item='nested.%d' % j)
> nested.complete()
> progress.complete()
>
> topiclabel = 'loop'
> def getloopitem(i):
> return 'loop.%d' % i
>
> EOF
$ cp $HGRCPATH $HGRCPATH.orig
$ echo "[extensions]" >> $HGRCPATH
$ echo "progress=" >> $HGRCPATH
$ echo "loop=`pwd`/loop.py" >> $HGRCPATH
$ echo "[progress]" >> $HGRCPATH
$ echo "format = topic bar number" >> $HGRCPATH
$ echo "assume-tty=1" >> $HGRCPATH
$ echo "width=60" >> $HGRCPATH
test default params, display nothing because of delay
$ hg -y loop 3
$ echo "delay=0" >> $HGRCPATH
$ echo "refresh=0" >> $HGRCPATH
test with delay=0, refresh=0
$ hg -y loop 3
\r (no-eol) (esc)
loop [ ] 0/3\r (no-eol) (esc)
loop [===============> ] 1/3\r (no-eol) (esc)
loop [===============================> ] 2/3\r (no-eol) (esc)
\r (no-eol) (esc)
no progress with --quiet
$ hg -y loop 3 --quiet
test plain mode exception
$ HGPLAINEXCEPT=progress hg -y loop 1
\r (no-eol) (esc)
loop [ ] 0/1\r (no-eol) (esc)
\r (no-eol) (esc)
test nested short-lived topics (which shouldn't display with nestdelay):
$ hg -y loop 3 --nested
\r (no-eol) (esc)
loop [ ] 0/3\r (no-eol) (esc)
loop [===============> ] 1/3\r (no-eol) (esc)
loop [===============================> ] 2/3\r (no-eol) (esc)
\r (no-eol) (esc)
Test nested long-lived topic which has the same name as a short-lived
peer. We shouldn't get stuck showing the short-lived inner steps, and
should go back to skipping the inner steps when the slow nested step
finishes.
$ hg -y loop 7 --nested
\r (no-eol) (esc)
loop [ ] 0/7\r (no-eol) (esc)
loop [=====> ] 1/7\r (no-eol) (esc)
loop [============> ] 2/7\r (no-eol) (esc)
loop [===================> ] 3/7\r (no-eol) (esc)
loop [==========================> ] 4/7\r (no-eol) (esc)
nested [==========================> ] 3/5\r (no-eol) (esc)
nested [===================================> ] 4/5\r (no-eol) (esc)
loop [=================================> ] 5/7\r (no-eol) (esc)
loop [========================================> ] 6/7\r (no-eol) (esc)
\r (no-eol) (esc)
$ hg --config progress.changedelay=0 -y loop 3 --nested
\r (no-eol) (esc)
loop [ ] 0/3\r (no-eol) (esc)
nested [ ] 0/2\r (no-eol) (esc)
nested [======================> ] 1/2\r (no-eol) (esc)
loop [===============> ] 1/3\r (no-eol) (esc)
nested [ ] 0/2\r (no-eol) (esc)
nested [======================> ] 1/2\r (no-eol) (esc)
loop [===============================> ] 2/3\r (no-eol) (esc)
nested [ ] 0/2\r (no-eol) (esc)
nested [======================> ] 1/2\r (no-eol) (esc)
\r (no-eol) (esc)
test two topics being printed in parallel (as when we're doing a local
--pull clone, where you get the unbundle and bundle progress at the
same time):
$ hg loop 3 --parallel
\r (no-eol) (esc)
loop [ ] 0/3\r (no-eol) (esc)
loop [===============> ] 1/3\r (no-eol) (esc)
loop [===============================> ] 2/3\r (no-eol) (esc)
\r (no-eol) (esc)
test refresh is taken in account
$ hg -y --config progress.refresh=100 loop 3
test format options 1
$ hg -y --config 'progress.format=number topic item+2' loop 2
\r (no-eol) (esc)
0/2 loop lo\r (no-eol) (esc)
1/2 loop lo\r (no-eol) (esc)
\r (no-eol) (esc)
test format options 2
$ hg -y --config 'progress.format=number item-3 bar' loop 2
\r (no-eol) (esc)
0/2 p.0 [ ]\r (no-eol) (esc)
1/2 p.1 [=======================> ]\r (no-eol) (esc)
\r (no-eol) (esc)
test format options and indeterminate progress
$ hg -y --config 'progress.format=number item bar' loop -- -2
\r (no-eol) (esc)
0 loop.0 [ <=> ]\r (no-eol) (esc)
1 loop.1 [ <=> ]\r (no-eol) (esc)
\r (no-eol) (esc)
make sure things don't fall over if count > total
$ hg -y loop --total 4 6
\r (no-eol) (esc)
loop [ ] 0/4\r (no-eol) (esc)
loop [===========> ] 1/4\r (no-eol) (esc)
loop [=======================> ] 2/4\r (no-eol) (esc)
loop [===================================> ] 3/4\r (no-eol) (esc)
loop [===============================================>] 4/4\r (no-eol) (esc)
loop [ <=> ] 5/4\r (no-eol) (esc)
\r (no-eol) (esc)
test immediate progress completion
$ hg -y loop 0
test delay time estimates
#if no-chg
$ cp $HGRCPATH.orig $HGRCPATH
$ echo "[extensions]" >> $HGRCPATH
$ echo "mocktime=$TESTDIR/mocktime.py" >> $HGRCPATH
$ echo "progress=" >> $HGRCPATH
$ echo "loop=`pwd`/loop.py" >> $HGRCPATH
$ echo "[progress]" >> $HGRCPATH
$ echo "assume-tty=1" >> $HGRCPATH
$ echo "delay=25" >> $HGRCPATH
$ echo "width=60" >> $HGRCPATH
$ MOCKTIME=11 hg -y loop 8
\r (no-eol) (esc)
loop [=========> ] 2/8 1m07s\r (no-eol) (esc)
loop [===============> ] 3/8 56s\r (no-eol) (esc)
loop [=====================> ] 4/8 45s\r (no-eol) (esc)
loop [==========================> ] 5/8 34s\r (no-eol) (esc)
loop [================================> ] 6/8 23s\r (no-eol) (esc)
loop [=====================================> ] 7/8 12s\r (no-eol) (esc)
\r (no-eol) (esc)
$ MOCKTIME=10000 hg -y loop 4
\r (no-eol) (esc)
loop [ ] 0/4\r (no-eol) (esc)
loop [=========> ] 1/4 8h21m\r (no-eol) (esc)
loop [====================> ] 2/4 5h34m\r (no-eol) (esc)
loop [==============================> ] 3/4 2h47m\r (no-eol) (esc)
\r (no-eol) (esc)
$ MOCKTIME=1000000 hg -y loop 4
\r (no-eol) (esc)
loop [ ] 0/4\r (no-eol) (esc)
loop [=========> ] 1/4 5w00d\r (no-eol) (esc)
loop [====================> ] 2/4 3w03d\r (no-eol) (esc)
loop [=============================> ] 3/4 11d14h\r (no-eol) (esc)
\r (no-eol) (esc)
$ MOCKTIME=14000000 hg -y loop 4
\r (no-eol) (esc)
loop [ ] 0/4\r (no-eol) (esc)
loop [=========> ] 1/4 1y18w\r (no-eol) (esc)
loop [===================> ] 2/4 46w03d\r (no-eol) (esc)
loop [=============================> ] 3/4 23w02d\r (no-eol) (esc)
\r (no-eol) (esc)
Non-linear progress:
$ MOCKTIME='20 20 20 20 20 20 20 20 20 20 500 500 500 500 500 20 20 20 20 20' hg -y loop 20
\r (no-eol) (esc)
loop [=> ] 1/20 6m21s\r (no-eol) (esc)
loop [===> ] 2/20 6m01s\r (no-eol) (esc)
loop [=====> ] 3/20 5m41s\r (no-eol) (esc)
loop [=======> ] 4/20 5m21s\r (no-eol) (esc)
loop [=========> ] 5/20 5m01s\r (no-eol) (esc)
loop [===========> ] 6/20 4m41s\r (no-eol) (esc)
loop [=============> ] 7/20 4m21s\r (no-eol) (esc)
loop [===============> ] 8/20 4m01s\r (no-eol) (esc)
loop [================> ] 9/20 25m40s\r (no-eol) (esc)
loop [===================> ] 10/20 1h06m\r (no-eol) (esc)
loop [=====================> ] 11/20 1h13m\r (no-eol) (esc)
loop [=======================> ] 12/20 1h07m\r (no-eol) (esc)
loop [========================> ] 13/20 58m19s\r (no-eol) (esc)
loop [===========================> ] 14/20 7m09s\r (no-eol) (esc)
loop [=============================> ] 15/20 3m38s\r (no-eol) (esc)
loop [===============================> ] 16/20 2m15s\r (no-eol) (esc)
loop [=================================> ] 17/20 1m27s\r (no-eol) (esc)
loop [====================================> ] 18/20 52s\r (no-eol) (esc)
loop [======================================> ] 19/20 25s\r (no-eol) (esc)
\r (no-eol) (esc)
Time estimates should not fail when there's no end point:
$ MOCKTIME=11 hg -y loop -- -4
\r (no-eol) (esc)
loop [ <=> ] 2\r (no-eol) (esc)
loop [ <=> ] 3\r (no-eol) (esc)
\r (no-eol) (esc)
#endif
test line trimming by '[progress] width', when progress topic contains
multi-byte characters, of which length of byte sequence and columns in
display are different from each other.
$ cp $HGRCPATH.orig $HGRCPATH
$ cat >> $HGRCPATH <<EOF
> [extensions]
> progress=
> loop=`pwd`/loop.py
> [progress]
> assume-tty = 1
> delay = 0
> refresh = 0
> EOF
$ rm -f loop.pyc
$ cat >> loop.py <<EOF
> # use non-ascii characters as topic label of progress
> # 2 x 4 = 8 columns, but 3 x 4 = 12 bytes
> topiclabel = u'\u3042\u3044\u3046\u3048'.encode('utf-8')
> EOF
$ cat >> $HGRCPATH <<EOF
> [progress]
> format = topic number
> width= 12
> EOF
$ hg --encoding utf-8 -y loop --total 3 3
\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 0/3\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 1/3\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 2/3\r (no-eol) (esc)
\r (no-eol) (esc)
test calculation of bar width, when progress topic contains multi-byte
characters, of which length of byte sequence and columns in display
are different from each other.
$ cat >> $HGRCPATH <<EOF
> [progress]
> format = topic bar
> width= 21
> # progwidth should be 9 (= 21 - (8+1) - 3)
> EOF
$ hg --encoding utf-8 -y loop --total 3 3
\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 [ ]\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 [==> ]\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88 [=====> ]\r (no-eol) (esc)
\r (no-eol) (esc)
test trimming progress items, when they contain multi-byte characters,
of which length of byte sequence and columns in display are different
from each other.
$ rm -f loop.pyc
$ rm -Rf __pycache__
$ cat >> loop.py <<EOF
> # use non-ascii characters as loop items of progress
> loopitems = [
> u'\u3042\u3044'.encode('utf-8'), # 2 x 2 = 4 columns
> u'\u3042\u3044\u3046'.encode('utf-8'), # 2 x 3 = 6 columns
> u'\u3042\u3044\u3046\u3048'.encode('utf-8'), # 2 x 4 = 8 columns
> ]
> def getloopitem(i):
> return loopitems[i % len(loopitems)]
> EOF
$ cat >> $HGRCPATH <<EOF
> [progress]
> # trim at tail side
> format = item+6
> EOF
$ hg --encoding utf-8 -y loop --total 3 3
\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84 \r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\r (no-eol) (esc)
\r (no-eol) (esc)
$ cat >> $HGRCPATH <<EOF
> [progress]
> # trim at left side
> format = item-6
> EOF
$ hg --encoding utf-8 -y loop --total 3 3
\r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84 \r (no-eol) (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\r (no-eol) (esc)
\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\r (no-eol) (esc)
\r (no-eol) (esc)