filecache: use try-except for faster __dict__ lookup
Python function call is slow, and the cost could be significant here.
$ hg perfrevset 'branch(tip)' -R mercurial
(orig) wall 0.139511 comb 0.140000 user 0.140000 sys 0.000000 (best of 66)
(this) wall 0.114195 comb 0.110000 user 0.110000 sys 0.000000 (best of 81)
--- a/mercurial/localrepo.py Thu Oct 18 19:57:30 2018 -0700
+++ b/mercurial/localrepo.py Sat Oct 20 19:13:05 2018 +0900
@@ -91,7 +91,13 @@
def __get__(self, repo, type=None):
if repo is None:
return self
- return super(_basefilecache, self).__get__(repo.unfiltered(), type)
+ # inlined the fast path as the cost of function call matters
+ unfi = repo.unfiltered()
+ try:
+ return unfi.__dict__[self.sname]
+ except KeyError:
+ pass
+ return super(_basefilecache, self).__get__(unfi, type)
def __set__(self, repo, value):
return super(_basefilecache, self).__set__(repo.unfiltered(), value)
def __delete__(self, repo):
--- a/mercurial/scmutil.py Thu Oct 18 19:57:30 2018 -0700
+++ b/mercurial/scmutil.py Sat Oct 20 19:13:05 2018 +0900
@@ -1292,9 +1292,10 @@
if obj is None:
return self
# do we need to check if the file changed?
- if self.sname in obj.__dict__:
- assert self.name in obj._filecache, self.name
+ try:
return obj.__dict__[self.sname]
+ except KeyError:
+ pass
entry = obj._filecache.get(self.name)