Mercurial > hg
view tests/test-pull-branch.t @ 16120:47ee41fcf42b
largefiles: optimize update speed by only updating changed largefiles
Historically, during 'hg update', every largefile in the working copy was
hashed (which is a very expensive operation on big files) and any
largefiles that did not have a hash that matched their standin were
updated.
This patch optimizes 'hg update' by keeping track of what standins have
changed between the old and new revisions, and only updating the largefiles
that have changed. This saves a lot of time by avoiding the unecessary
calculation of a list of sha1 hashes for big files.
With this patch, the time 'hg update' takes to complete is a function of
how many largefiles need to be updated and what their size is.
Performance tests on a repository with about 80 largefiles ranging from
a few MB to about 97 MB are shown below. The tests show how long it takes
to run 'hg update' with no changes actually being updated.
Mercurial 2.1 release:
$ time hg update
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
getting changed largefiles
0 largefiles updated, 0 removed
real 0m10.045s
user 0m9.367s
sys 0m0.674s
With this patch:
$ time hg update
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
real 0m0.965s
user 0m0.845s
sys 0m0.115s
The same repsoitory, without the largefiles extension enabled:
$ time hg update
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
real 0m0.799s
user 0m0.684s
sys 0m0.111s
So before the patch, 'hg update' with no changes was approximately 9.25s
slower with largefiles enabled. With this patch, it is approximately 0.165s
slower.
| author | Na'Tosha Bard <natosha@unity3d.com> |
|---|---|
| date | Mon, 13 Feb 2012 18:37:07 +0100 |
| parents | 41885892796e |
| children | f2719b387380 |
line wrap: on
line source
$ hg init t $ cd t $ echo 1 > foo $ hg ci -Am1 # 0 adding foo $ hg branch branchA marked working directory as branch branchA (branches are permanent and global, did you want a bookmark?) $ echo a1 > foo $ hg ci -ma1 # 1 $ cd .. $ hg init tt $ cd tt $ hg pull ../t pulling from ../t requesting all changes adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files (run 'hg update' to get a working copy) $ hg up branchA 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd ../t $ echo a2 > foo $ hg ci -ma2 # 2 Create branch B: $ hg up 0 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg branch branchB marked working directory as branch branchB (branches are permanent and global, did you want a bookmark?) $ echo b1 > foo $ hg ci -mb1 # 3 $ cd ../tt A new branch is there $ hg pull -u ../t pulling from ../t searching for changes adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files (+1 heads) 1 files updated, 0 files merged, 0 files removed, 0 files unresolved Develop both branches: $ cd ../t $ hg up branchA 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a3 > foo $ hg ci -ma3 # 4 $ hg up branchB 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo b2 > foo $ hg ci -mb2 # 5 $ cd ../tt Should succeed, no new heads: $ hg pull -u ../t pulling from ../t searching for changes adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files 1 files updated, 0 files merged, 0 files removed, 0 files unresolved Add a head on other branch: $ cd ../t $ hg up branchA 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a4 > foo $ hg ci -ma4 # 6 $ hg up branchB 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo b3.1 > foo $ hg ci -m b3.1 # 7 $ hg up 5 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo b3.2 > foo $ hg ci -m b3.2 # 8 created new head $ cd ../tt Should succeed because there is only one head on our branch: $ hg pull -u ../t pulling from ../t searching for changes adding changesets adding manifests adding file changes added 3 changesets with 3 changes to 1 files (+1 heads) 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd ../t $ hg up -C branchA 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a5.1 > foo $ hg ci -ma5.1 # 9 $ hg up 6 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a5.2 > foo $ hg ci -ma5.2 # 10 created new head $ hg up 7 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo b4.1 > foo $ hg ci -m b4.1 # 11 $ hg up -C 8 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo b4.2 > foo $ hg ci -m b4.2 # 12 $ cd ../tt $ hg pull -u ../t pulling from ../t searching for changes adding changesets adding manifests adding file changes added 4 changesets with 4 changes to 1 files (+1 heads) 1 files updated, 0 files merged, 0 files removed, 0 files unresolved Make changes on new branch on tt $ hg up 6 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg branch branchC marked working directory as branch branchC (branches are permanent and global, did you want a bookmark?) $ echo b1 > bar $ hg ci -Am "commit on branchC on tt" adding bar Make changes on default branch on t $ cd ../t $ hg up -C default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a1 > bar $ hg ci -Am "commit on default on t" adding bar Pull branchC from tt $ hg pull ../tt pulling from ../tt searching for changes adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files (+1 heads) (run 'hg heads' to see heads) Make changes on default and branchC on tt $ cd ../tt $ hg pull ../t pulling from ../t searching for changes adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files (+1 heads) (run 'hg heads' to see heads) $ hg up -C default 2 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a1 > bar1 $ hg ci -Am "commit on default on tt" adding bar1 $ hg up branchC 2 files updated, 0 files merged, 1 files removed, 0 files unresolved $ echo a1 > bar2 $ hg ci -Am "commit on branchC on tt" adding bar2 Make changes on default and branchC on t $ cd ../t $ hg up default 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo a1 > bar3 $ hg ci -Am "commit on default on t" adding bar3 $ hg up branchC 2 files updated, 0 files merged, 1 files removed, 0 files unresolved $ echo a1 > bar4 $ hg ci -Am "commit on branchC on tt" adding bar4 Pull from tt $ hg pull ../tt pulling from ../tt searching for changes adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 2 files (+2 heads) (run 'hg heads .' to see heads, 'hg merge' to merge)