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Differential D7122

copies: avoid instancing more changectx to access parent revisions
ClosedPublic

Authored by marmoute on Oct 16 2019, 12:54 PM.

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Details

Reviewers

martinvonz

Group Reviewers

hg-reviewers

Commits

rHG181d28ba05da: copies: avoid instancing more changectx to access parent revisions
rHG6b43c7be2d15: copies: avoid instancing more changectx to access parent revisions

Summary

We just need to know the revision numbers of the parents, creating full context
is needlessly expensive.

This provide a small, but noticeable performance boost.

revision: large amount; added files: large amount; rename small amount; c3b14617fbd7 9ba6ab77fd29
before: ! wall 2.885636 comb 2.900000 user 2.870000 sys 0.030000 (median of 10)
after: ! wall 2.702270 comb 2.710000 user 2.690000 sys 0.020000 (median of 10)
revision: large amount; added files: small amount; rename small amount; c3b14617fbd7 f650a9b140d2
before: ! wall 4.298271 comb 4.290000 user 4.240000 sys 0.050000 (median of 10)
after: ! wall 3.976610 comb 3.970000 user 3.920000 sys 0.050000 (median of 10)
revision: large amount; added files: large amount; rename large amount; 08ea3258278e d9fa043f30c0
before: ! wall 0.773397 comb 0.770000 user 0.770000 sys 0.000000 (median of 11)
after: ! wall 0.701634 comb 0.700000 user 0.700000 sys 0.000000 (median of 13)
revision: small amount; added files: large amount; rename large amount; df6f7a526b60 a83dc6a2d56f
before: ! wall 0.013585 comb 0.010000 user 0.010000 sys 0.000000 (median of 217)
after: ! wall 0.013550 comb 0.010000 user 0.010000 sys 0.000000 (median of 218)
revision: small amount; added files: large amount; rename small amount; 4aa4e1f8e19a 169138063d63
before: ! wall 0.003202 comb 0.000000 user 0.000000 sys 0.000000 (median of 929)
after: ! wall 0.002993 comb 0.010000 user 0.010000 sys 0.000000 (median of 992)
revision: small amount; added files: small amount; rename small amount; 4bc173b045a6 964879152e2e
before: ! wall 0.000077 comb 0.000000 user 0.000000 sys 0.000000 (median of 12060)
after: ! wall 0.000072 comb 0.000000 user 0.000000 sys 0.000000 (median of 12804)
revision: medium amount; added files: large amount; rename medium amount; c95f1ced15f2 2c68e87c3efe
before: ! wall 0.510614 comb 0.500000 user 0.500000 sys 0.000000 (median of 18)
after: ! wall 0.473681 comb 0.470000 user 0.470000 sys 0.000000 (median of 20)
revision: medium amount; added files: medium amount; rename small amount; d343da0c55a8 d7746d32bf9d
before: ! wall 0.126552 comb 0.130000 user 0.130000 sys 0.000000 (median of 77)
after: ! wall 0.115240 comb 0.110000 user 0.110000 sys 0.000000 (median of 85)

Diff Detail

Repository

rHG Mercurial

Lint

Automatic diff as part of commit; lint not applicable.

Unit

Automatic diff as part of commit; unit tests not applicable.

Event Timeline

marmoute created this revision.Oct 16 2019, 12:54 PM

Herald added a reviewer: hg-reviewers. · View Herald TranscriptOct 16 2019, 12:54 PM

Herald added a subscriber: mercurial-devel. · View Herald Transcript

marmoute added a child revision: D7070: copies: extract data extraction into a `revinfo` function.Oct 16 2019, 12:54 PM

In my copies-in-changesets version of mozilla-unified, this makes a very significant difference:

before:
! wall 4.485065 comb 4.490000 user 4.440000 sys 0.050000 (best of 10)
after:
! wall 3.695755 comb 3.690000 user 3.660000 sys 0.030000 (best of 10)

This revision is now accepted and ready to land.Oct 16 2019, 1:19 PM

marmoute added a commit: rHG6b43c7be2d15: copies: avoid instancing more changectx to access parent revisions.Oct 16 2019, 1:33 PM

Closed by commit rHG6b43c7be2d15: copies: avoid instancing more changectx to access parent revisions (authored by marmoute). · Explain Why

This revision was automatically updated to reflect the committed changes.

marmoute updated this revision to Diff 17272.Oct 16 2019, 5:49 PM

marmoute added a commit: rHG181d28ba05da: copies: avoid instancing more changectx to access parent revisions.Oct 16 2019, 10:37 PM

Revision Contents
Changeset List

			Path	Packages
M			mercurial/copies.py (5 lines)

Diff	ID	Description	Created	Lint	Unit
Base		Base
Diff 1	17241		Oct 16 2019, 12:54 PM	★	★
Diff 2	17248	rHG6b43c7be2d15f8ab62e30d97a99d8b363a95c780	Oct 16 2019, 11:49 AM	★	★
Diff 3	17272		Oct 16 2019, 5:49 PM	★	★

Status	Author	Revision
Closed	marmoute	D7131 copies: simplify chain loop
Closed	marmoute	D7127 sidedatacopies: only fetch information once for merge
Closed	marmoute	D7124 copies: move from a copy on branchpoint to a copy on write approach
Closed	marmoute	D7076 copies: compute the exact set of revision to walk
Closed	marmoute	D7075 copies: add an explicit test using multiple roots
Closed	marmoute	D7074 sidedatacopies: fast path data fetching if revision has no sidedata
Abandoned	marmoute	D7073 revlog: introduce a `_uncheckedflags` shortcut
Closed	marmoute	D7072 sidedatacopies: directly fetch copies information from sidedata
Closed	marmoute	D7123 copies: use an unfiltered repository for the changeset centric algorithm
Abandoned	marmoute	D7071 copies: use unchecked parentrevs function to access parent
Closed	marmoute	D7070 copies: extract data extraction into a `revinfo` function
Closed	marmoute	D7122 copies: avoid instancing more changectx to access parent revisions
Closed	marmoute	D7121 copies: get copies information directly from _copies

Diff 17248

mercurial/copies.py

	alwaysmatch = match.always()			alwaysmatch = match.always()
	while work:			while work:
	r = heapq.heappop(work)			r = heapq.heappop(work)
	copies = all_copies.pop(r)			copies = all_copies.pop(r)
	if r == b.rev():			if r == b.rev():
	return copies			return copies
	for i, c in enumerate(children[r]):			for i, c in enumerate(children[r]):
	childctx = repo[c]			childctx = repo[c]
				p1, p2 = cl.parentrevs(c)
	p1copies, p2copies = childctx._copies			p1copies, p2copies = childctx._copies
	if r == childctx.p1().rev():			if r == p1:
	parent = 1			parent = 1
	childcopies = p1copies			childcopies = p1copies
	else:			else:
	assert r == childctx.p2().rev()			assert r == p2
	parent = 2			parent = 2
	childcopies = p2copies			childcopies = p2copies
	if not alwaysmatch:			if not alwaysmatch:
	childcopies = {			childcopies = {
	dst: src for dst, src in childcopies.items() if match(dst)			dst: src for dst, src in childcopies.items() if match(dst)
	}			}
	# Copy the dict only if later iterations will also need it			# Copy the dict only if later iterations will also need it
	if i != len(children[r]) - 1:			if i != len(children[r]) - 1: