bzr diff in 2a to historical revision too slow
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Bazaar |
Confirmed
|
Medium
|
Unassigned |
Bug Description
Per bug #213718, Rob says I should file this. It's quicker than whatever the example in question was, but it should be indicative:
$ cd launchpad
$ echo Cold cache; time bzr diff -r 7675.852.10 > /dev/null
Cold cache
real 1m0.019s
user 0m31.734s
sys 0m2.100s
$ echo Hot cache; time bzr diff -r 7675.852.10 > /dev/null
real 0m22.269s
user 0m21.033s
sys 0m1.176s
(FWIW, I think at the time I was trying to discover why 'launchpad/
(Be-aware that the Launchpad bzr tree is 280MB+ may take 3+ hours to fetch via 'bzr get lp:launchpad').
I tested this and it did take 28 seconds on a fairly cold cache (without dropping buffers.) It produces roughly an 8MB diff. (You realize this gives the whole diff to your working tree, not the changes in that one commit?)
For me, getting the diff from the wt to its basis revision is 0.4s, which is more what it should be.
Paul, in general if you're reporting a performance problem, attaching the lsprof output helps diagnosis. (We should mention that in the bug-filing guidelines...)