Mercurial > hg-stable
view tests/test-mq-guards.t @ 26457:7e81305092a0
demandimport: replace more references to _demandmod instances
_demandmod instances may be referenced by multiple importing modules.
Before this patch, the _demandmod instance only maintained a reference
to its first consumer when using the "from X import Y" syntax. This is
because we only created a single _demandmod instance (attached to the
parent X module). If multiple modules A and B performed
"from X import Y", we'd produce a single _demandmod instance
"demandmod" with the following references:
X.Y = <demandmod>
A.Y = <demandmod>
B.Y = <demandmod>
The locals from the first consumer (A) would be stored in <demandmod1>.
When <demandmod1> was loaded, we'd look at the locals for the first
consumer and replace the symbol, if necessary. This resulted in state:
X.Y = <module>
A.Y = <module>
B.Y = <demandmod>
B's reference to Y wasn't updated and was still using the proxy object
because we just didn't record that B had a reference to <demandmod> that
needed updating!
With this patch, we add support for tracking which modules in addition
to the initial importer have a reference to the _demandmod instance and
we replace those references at module load time.
In the case of posix.py, this fixes an issue where the "encoding" module
was being proxied, resulting in hundreds of thousands of
__getattribute__ lookups on the _demandmod instance during dirstate
operations on mozilla-central, speeding up execution by many
milliseconds. There are likely several other operation that benefit from
this change as well.
The new mechanism isn't perfect: references in locals (not globals) may
likely linger. So, if there is an import inside a function and a symbol
from that module is used in a hot loop, we could have unwanted overhead
from proxying through _demandmod. Non-global imports are discouraged
anyway. So hopefully this isn't a big deal in practice. We could
potentially deploy a code checker that bans use of attribute lookups of
function-level-imported modules inside loops.
This deficiency in theory could be avoided by storing the set of globals
and locals dicts to update in the _demandmod instance. However, I tried
this and it didn't work. One reason is that some globals are _demandmod
instances. We could work around this, but it's a bit more work. There
also might be other module import foo at play. The solution as
implemented is better than what we had and IMO is good enough for the
time being.
It's worth noting that this sub-optimal behavior was made worse by the
introduction of absolute_import and its recommended "from . import X"
syntax for importing modules from the "mercurial" package. If we ever
wrote performance tests, measuring the amount of module imports and
__getattribute__ proxy calls through _demandmod instances would be
something I'd have it check.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sun, 04 Oct 2015 11:17:43 -0700 |
parents | a387b0390082 |
children | 55c6ebd11cb9 |
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$ echo "[extensions]" >> $HGRCPATH $ echo "mq=" >> $HGRCPATH $ hg init $ hg qinit $ echo x > x $ hg ci -Ama adding x $ hg qnew a.patch $ echo a > a $ hg add a $ hg qrefresh $ hg qnew b.patch $ echo b > b $ hg add b $ hg qrefresh $ hg qnew c.patch $ echo c > c $ hg add c $ hg qrefresh $ hg qpop -a popping c.patch popping b.patch popping a.patch patch queue now empty should fail $ hg qguard does-not-exist.patch +bleh abort: no patch named does-not-exist.patch [255] should fail $ hg qguard +fail abort: no patches applied [255] $ hg qpush applying a.patch now at: a.patch should guard a.patch $ hg qguard +a should print +a $ hg qguard a.patch: +a $ hg qpop popping a.patch patch queue now empty should fail $ hg qpush a.patch cannot push 'a.patch' - guarded by '+a' [1] $ hg qguard a.patch a.patch: +a should push b.patch $ hg qpush applying b.patch now at: b.patch $ hg qpop popping b.patch patch queue now empty test selection of an empty guard $ hg qselect "" abort: guard cannot be an empty string [255] $ hg qselect a number of unguarded, unapplied patches has changed from 2 to 3 should push a.patch $ hg qpush applying a.patch now at: a.patch $ hg qguard -- c.patch -a should print -a $ hg qguard c.patch c.patch: -a should skip c.patch $ hg qpush -a applying b.patch skipping c.patch - guarded by '-a' now at: b.patch $ hg qnext all patches applied [1] should display b.patch $ hg qtop b.patch $ hg qguard -n c.patch should push c.patch $ hg qpush -a applying c.patch now at: c.patch $ hg qpop -a popping c.patch popping b.patch popping a.patch patch queue now empty $ hg qselect -n guards deactivated number of unguarded, unapplied patches has changed from 3 to 2 should push all $ hg qpush -a applying b.patch applying c.patch now at: c.patch $ hg qpop -a popping c.patch popping b.patch patch queue now empty $ hg qguard a.patch +1 $ hg qguard b.patch +2 $ hg qselect 1 number of unguarded, unapplied patches has changed from 1 to 2 should push a.patch, not b.patch $ hg qpush applying a.patch now at: a.patch $ hg qpush applying c.patch now at: c.patch $ hg qpop -a popping c.patch popping a.patch patch queue now empty $ hg qselect 2 should push b.patch $ hg qpush applying b.patch now at: b.patch $ hg qpush -a applying c.patch now at: c.patch $ hg qprev b.patch Used to be an issue with holes in the patch sequence So, put one hole on the base and ask for topmost patch. $ hg qtop c.patch $ hg qpop -a popping c.patch popping b.patch patch queue now empty $ hg qselect 1 2 number of unguarded, unapplied patches has changed from 2 to 3 should push a.patch, b.patch $ hg qpush applying a.patch now at: a.patch $ hg qpush applying b.patch now at: b.patch $ hg qpop -a popping b.patch popping a.patch patch queue now empty $ hg qguard -- a.patch +1 +2 -3 $ hg qselect 1 2 3 number of unguarded, unapplied patches has changed from 3 to 2 list patches and guards $ hg qguard -l a.patch: +1 +2 -3 b.patch: +2 c.patch: unguarded have at least one patch applied to test coloring $ hg qpush applying b.patch now at: b.patch list patches and guards with color $ hg --config extensions.color= qguard --config color.mode=ansi \ > -l --color=always \x1b[0;30;1ma.patch\x1b[0m: \x1b[0;33m+1\x1b[0m \x1b[0;33m+2\x1b[0m \x1b[0;31m-3\x1b[0m (esc) \x1b[0;34;1;4mb.patch\x1b[0m: \x1b[0;33m+2\x1b[0m (esc) \x1b[0;30;1mc.patch\x1b[0m: \x1b[0;32munguarded\x1b[0m (esc) should pop b.patch $ hg qpop popping b.patch patch queue now empty list series $ hg qseries -v 0 G a.patch 1 U b.patch 2 U c.patch list guards $ hg qselect 1 2 3 should push b.patch $ hg qpush applying b.patch now at: b.patch $ hg qpush -a applying c.patch now at: c.patch $ hg qselect -n --reapply -v guards deactivated popping guarded patches popping c.patch popping b.patch patch queue now empty reapplying unguarded patches skipping a.patch - guarded by '+1' '+2' skipping b.patch - guarded by '+2' skipping a.patch - guarded by '+1' '+2' skipping b.patch - guarded by '+2' applying c.patch patching file c adding c committing files: c committing manifest committing changelog now at: c.patch guards in series file: +1 +2 -3 $ hg qselect -s +1 +2 -3 should show c.patch $ hg qapplied c.patch $ hg qrename a.patch new.patch should show : new.patch: +1 +2 -3 b.patch: +2 c.patch: unguarded $ hg qguard -l new.patch: +1 +2 -3 b.patch: +2 c.patch: unguarded $ hg qnew d.patch $ hg qpop popping d.patch now at: c.patch should show new.patch and b.patch as Guarded, c.patch as Applied and d.patch as Unapplied $ hg qseries -v 0 G new.patch 1 G b.patch 2 A c.patch 3 U d.patch qseries again, but with color $ hg --config extensions.color= --config color.mode=ansi qseries -v --color=always 0 G \x1b[0;30;1mnew.patch\x1b[0m (esc) 1 G \x1b[0;30;1mb.patch\x1b[0m (esc) 2 A \x1b[0;34;1;4mc.patch\x1b[0m (esc) 3 U \x1b[0;30;1md.patch\x1b[0m (esc) $ hg qguard d.patch +2 new.patch, b.patch: Guarded. c.patch: Applied. d.patch: Guarded. $ hg qseries -v 0 G new.patch 1 G b.patch 2 A c.patch 3 G d.patch $ qappunappv() > { > for command in qapplied "qapplied -v" qunapplied "qunapplied -v"; do > echo % hg $command > hg $command > done > } $ hg qpop -a popping c.patch patch queue now empty $ hg qguard -l new.patch: +1 +2 -3 b.patch: +2 c.patch: unguarded d.patch: +2 $ qappunappv % hg qapplied % hg qapplied -v % hg qunapplied c.patch % hg qunapplied -v 0 G new.patch 1 G b.patch 2 U c.patch 3 G d.patch $ hg qselect 1 number of unguarded, unapplied patches has changed from 1 to 2 $ qappunappv % hg qapplied % hg qapplied -v % hg qunapplied new.patch c.patch % hg qunapplied -v 0 U new.patch 1 G b.patch 2 U c.patch 3 G d.patch $ hg qpush -a applying new.patch skipping b.patch - guarded by '+2' applying c.patch skipping d.patch - guarded by '+2' now at: c.patch $ qappunappv % hg qapplied new.patch c.patch % hg qapplied -v 0 A new.patch 1 G b.patch 2 A c.patch % hg qunapplied % hg qunapplied -v 3 G d.patch $ hg qselect 2 number of unguarded, unapplied patches has changed from 0 to 1 $ qappunappv % hg qapplied new.patch c.patch % hg qapplied -v 0 A new.patch 1 U b.patch 2 A c.patch % hg qunapplied d.patch % hg qunapplied -v 3 U d.patch $ for patch in `hg qseries`; do > echo % hg qapplied $patch > hg qapplied $patch > echo % hg qunapplied $patch > hg qunapplied $patch > done % hg qapplied new.patch new.patch % hg qunapplied new.patch b.patch d.patch % hg qapplied b.patch new.patch % hg qunapplied b.patch d.patch % hg qapplied c.patch new.patch c.patch % hg qunapplied c.patch d.patch % hg qapplied d.patch new.patch c.patch % hg qunapplied d.patch hg qseries -m: only b.patch should be shown the guards file was not ignored in the past $ hg qdelete -k b.patch $ hg qseries -m b.patch hg qseries -m with color $ hg --config extensions.color= --config color.mode=ansi qseries -m --color=always \x1b[0;31;1mb.patch\x1b[0m (esc) excercise corner cases in "qselect --reapply" $ hg qpop -a popping c.patch popping new.patch patch queue now empty $ hg qguard -- new.patch -not-new $ hg qguard -- c.patch -not-c $ hg qguard -- d.patch -not-d $ hg qpush -a applying new.patch applying c.patch applying d.patch patch d.patch is empty now at: d.patch $ hg qguard -l new.patch: -not-new c.patch: -not-c d.patch: -not-d $ hg qselect --reapply not-d popping guarded patches popping d.patch now at: c.patch reapplying unguarded patches cannot push 'd.patch' - guarded by '-not-d' $ hg qser -v 0 A new.patch 1 A c.patch 2 G d.patch $ hg qselect --reapply -n guards deactivated $ hg qpush applying d.patch patch d.patch is empty now at: d.patch $ hg qser -v 0 A new.patch 1 A c.patch 2 A d.patch $ hg qselect --reapply not-c popping guarded patches popping d.patch popping c.patch now at: new.patch reapplying unguarded patches applying d.patch patch d.patch is empty now at: d.patch $ hg qser -v 0 A new.patch 1 G c.patch 2 A d.patch $ hg qselect --reapply not-new popping guarded patches popping d.patch popping new.patch patch queue now empty reapplying unguarded patches applying c.patch applying d.patch patch d.patch is empty now at: d.patch $ hg qser -v 0 G new.patch 1 A c.patch 2 A d.patch test that qselect shows "number of guarded, applied patches" correctly $ hg qimport -q -e b.patch adding b.patch to series file $ hg qguard -- b.patch -not-b $ hg qpop -a -q patch queue now empty $ hg qunapplied -v 0 G new.patch 1 U c.patch 2 U d.patch 3 U b.patch $ hg qselect not-new not-c number of unguarded, unapplied patches has changed from 3 to 2 $ hg qpush -q -a patch d.patch is empty now at: b.patch $ hg qapplied -v 0 G new.patch 1 G c.patch 2 A d.patch 3 A b.patch $ hg qselect --none guards deactivated $ hg qselect not-new not-c not-d number of guarded, applied patches has changed from 0 to 1 test that "qselect --reapply" reapplies patches successfully when the already applied patch becomes unguarded and it follows the already guarded (= not yet applied) one. $ hg qpop -q -a patch queue now empty $ hg qselect not-new not-c number of unguarded, unapplied patches has changed from 1 to 2 $ hg qpush -q -a patch d.patch is empty now at: b.patch $ hg qapplied -v 0 G new.patch 1 G c.patch 2 A d.patch 3 A b.patch $ hg qselect -q --reapply not-c not-b now at: d.patch cannot push 'b.patch' - guarded by '-not-b' $ hg qseries -v 0 U new.patch 1 G c.patch 2 A d.patch 3 G b.patch test that "qselect --reapply" checks applied patches correctly when no applied patches becomes guarded but some of unapplied ones become unguarded. $ hg qpop -q -a patch queue now empty $ hg qselect not-new not-c not-d number of unguarded, unapplied patches has changed from 2 to 1 $ hg qpush -q -a now at: b.patch $ hg qapplied -v 0 G new.patch 1 G c.patch 2 G d.patch 3 A b.patch $ hg qselect -q --reapply not-new not-c $ hg qseries -v 0 G new.patch 1 G c.patch 2 U d.patch 3 A b.patch