Mercurial > public > mercurial-scm > hg-stable
comparison mercurial/revset.py @ 21939:f486001f9d6f stable
revset: optimize baseset.__sub__ (issue4313)
dd716807fd23 regressed performance of baseset.__sub__ by introducing
a lazyset. This patch restores that lost performance by eagerly
evaluating baseset.__sub__ if the other set is a baseset.
revsetbenchmark.py results impacted by this change:
revset #6: roots(0::tip)
0) wall 2.923473 comb 2.920000 user 2.920000 sys 0.000000 (best of 4)
1) wall 0.077614 comb 0.080000 user 0.080000 sys 0.000000 (best of 100)
revset #23: roots((0:tip)::)
0) wall 2.875178 comb 2.880000 user 2.880000 sys 0.000000 (best of 4)
1) wall 0.154519 comb 0.150000 user 0.150000 sys 0.000000 (best of 61)
On the author's machine, this slowdown manifested during evaluation of
'roots(%ln::)' in phases.retractboundary after unbundling the Firefox
repository. Using `time hg unbundle firefox.hg` as a benchmark:
Before: 8:00
After: 4:28
Delta: -3:32
For reference, the subset and cs baseset instances impacted by this
change were of lengths 193634 and 193627, respectively.
Explicit test coverage of roots(%ln::), while similar to the existing
roots(0::tip) benchmark, has been added.
| author | Gregory Szorc <gregory.szorc@gmail.com> |
|---|---|
| date | Thu, 24 Jul 2014 12:12:12 -0700 |
| parents | 7142e04b438e |
| children | 3efe3c2609e0 |
comparison
equal
deleted
inserted
replaced
| 21938:c8411fb5dfef | 21939:f486001f9d6f |
|---|---|
| 2230 | 2230 |
| 2231 def __sub__(self, other): | 2231 def __sub__(self, other): |
| 2232 """Returns a new object with the substraction of the two collections. | 2232 """Returns a new object with the substraction of the two collections. |
| 2233 | 2233 |
| 2234 This is part of the mandatory API for smartset.""" | 2234 This is part of the mandatory API for smartset.""" |
| 2235 # If we are operating on 2 baseset, do the computation now since all | |
| 2236 # data is available. The alternative is to involve a lazyset, which | |
| 2237 # may be slow. | |
| 2238 if isinstance(other, baseset): | |
| 2239 other = other.set() | |
| 2240 return baseset([x for x in self if x not in other]) | |
| 2241 | |
| 2235 return self.filter(lambda x: x not in other) | 2242 return self.filter(lambda x: x not in other) |
| 2236 | 2243 |
| 2237 def __and__(self, other): | 2244 def __and__(self, other): |
| 2238 """Returns a new object with the intersection of the two collections. | 2245 """Returns a new object with the intersection of the two collections. |
| 2239 | 2246 |