rust: peek_mut optim for lazy ancestors
This is one of the two optimizations that are also
present in the Python code: replacing pairs of pop/push
on the BinaryHeap by single updates, hence having it
under the hood maintain its consistency (sift) only once.
On Mozilla central, the measured gain (see details below)
is around 7%.
Creating the PeekMut object by calling peek_mut() right away
instead of peek() first is less efficient (gain is only 4%, stats
not included).
Our interpretation is that its creation has a cost which is vasted
in the cases where it ends by droping the value (Peekmut::pop()
just does self.heap.pop() anyway). On the other hand, the immutable
peek() is very fast: it's just taking a reference in the
underlying vector.
The Python version still has another optimization:
if parent(current) == current-1, then the heap doesn't need
to maintain its consistency, since we already know that
it's bigger than all the others in the heap.
Rust's BinaryHeap doesn't allow us to mutate its biggest
element with no housekeeping, but we tried it anyway, with a
copy of the BinaryHeap implementation with a dedicaded added
method: it's not worth the technical debt in our opinion
(we measured only a further 1.6% improvement).
One possible explanation would be that the sift is really fast
anyway in that case, whereas it's not in the case of Python,
because it's at least partly done in slow Python code.
Still it's possible that replacing BinaryHeap by something more
dedicated to discrete ordered types could be faster.
Measurements on mozilla-central:
Three runs of 'hg perfancestors' on the parent changeset:
Moyenne des médianes: 0.100587
! wall 0.100062 comb 0.100000 user 0.100000 sys 0.000000 (best of 98)
! wall 0.135804 comb 0.130000 user 0.130000 sys 0.000000 (max of 98)
! wall 0.102864 comb 0.102755 user 0.099286 sys 0.003469 (avg of 98)
! wall 0.101486 comb 0.110000 user 0.110000 sys 0.000000 (median of 98)
! wall 0.096804 comb 0.090000 user 0.090000 sys 0.000000 (best of 100)
! wall 0.132235 comb 0.130000 user 0.120000 sys 0.010000 (max of 100)
! wall 0.100258 comb 0.100300 user 0.096000 sys 0.004300 (avg of 100)
! wall 0.098384 comb 0.100000 user 0.100000 sys 0.000000 (median of 100)
! wall 0.099925 comb 0.100000 user 0.100000 sys 0.000000 (best of 98)
! wall 0.133518 comb 0.140000 user 0.130000 sys 0.010000 (max of 98)
! wall 0.102381 comb 0.102449 user 0.098265 sys 0.004184 (avg of 98)
! wall 0.101891 comb 0.090000 user 0.090000 sys 0.000000 (median of 98)
Mean of the medians: 0.100587
On the present changeset:
! wall 0.091344 comb 0.090000 user 0.090000 sys 0.000000 (best of 100)
! wall 0.122728 comb 0.120000 user 0.110000 sys 0.010000 (max of 100)
! wall 0.093268 comb 0.093300 user 0.089300 sys 0.004000 (avg of 100)
! wall 0.092567 comb 0.100000 user 0.090000 sys 0.010000 (median of 100)
! wall 0.093294 comb 0.080000 user 0.080000 sys 0.000000 (best of 100)
! wall 0.144887 comb 0.150000 user 0.140000 sys 0.010000 (max of 100)
! wall 0.097708 comb 0.097700 user 0.093400 sys 0.004300 (avg of 100)
! wall 0.094980 comb 0.100000 user 0.090000 sys 0.010000 (median of 100)
! wall 0.091262 comb 0.090000 user 0.080000 sys 0.010000 (best of 100)
! wall 0.123772 comb 0.130000 user 0.120000 sys 0.010000 (max of 100)
! wall 0.093188 comb 0.093200 user 0.089300 sys 0.003900 (avg of 100)
! wall 0.092364 comb 0.100000 user 0.090000 sys 0.010000 (median of 100)
Mean of the medians is 0.0933
Differential Revision: https://phab.mercurial-scm.org/D5358
$ 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=b'loopnum', total=total)
> other = ui.makeprogress(b'other', unit=b'othernum', total=total)
> for i in range(loops):
> progress.update(i, item=getloopitem(i))
> if opts.get('parallel'):
> other.update(i, item=b'other.%d' % i)
> if nested:
> nested_steps = 2
> if i and i % 4 == 0:
> nested_steps = 5
> nested = ui.makeprogress(b'nested', unit=b'nestnum',
> total=nested_steps)
> for j in range(nested_steps):
> nested.update(j, item=b'nested.%d' % j)
> nested.complete()
> progress.complete()
>
> topiclabel = b'loop'
> def getloopitem(i):
> return b'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)