Martin von Zweigbergk <martinvonz@google.com> [Wed, 19 Nov 2014 23:15:07 -0800] rev 23375
dirstate: speed up repeated missing directory checks
In a mozilla repo with tip at bb3ff09f52fe,
hg update tip~1000 && time hg revert -nq -r tip .
displays ~4:20 minutes. With tip~100, it runs in ~11 s. With revision
100000, it did not finish in 12 minutes.
Revert calls dirstate.status() with a matcher that matches each file
in the target revision. The main problem [1] lies in
dirstate._walkexplicit(), which looks for matching deleted directories
by checking whether each path is prefix of any path in the
dirstate. With m files in the dirstate and n files in the target
revision that are not in the dirstate, this is clearly O(m*n). Let's
improve by keeping a lazily initialized set of all the directories in
the dirstate, so the time becomes O(m+n).
After this patch, the 4:20 minutes become 5.5 s, while for a single
missing path, it slows down from 1.092 s to 1.150 s (best of 4). The
>12 min case becomes 5.8 s.
[1] A narrower optimization would be to make revert take the fast
path for '.' and '--all'.
Martin von Zweigbergk <martinvonz@google.com> [Wed, 19 Nov 2014 17:07:27 -0800] rev 23374
revert: access status fields by name rather than index
For better readability.
FUJIWARA Katsunori <foozy@lares.dti.ne.jp> [Wed, 19 Nov 2014 18:35:14 +0900] rev 23373
subrepo: remove "_getstorehashcachepath" referred by no other code paths
FUJIWARA Katsunori <foozy@lares.dti.ne.jp> [Wed, 19 Nov 2014 18:35:14 +0900] rev 23372
subrepo: replace direct file APIs around "writelines" by "vfs.writelines"
This patch also replaces "self._getstorehashcachepath" (building
absolute path up) by "self._getstorehashcachename" (building relative
path up), because "vfs.writelines" requires relative path.