[MERGE] faster log - hooray!

[Ian Clatworthy]

Karl Fogel wrote:
> Ian Clatworthy <ian.clatworthy at internode.on.net> writes:

>> Finally, log -v performance remains an issue. I plan/expect to
>> resolve that as part of the split-inventory format work. (I can't
>> see any obvious way to speed up the current implementation until
>> we can generate deltas faster.)

> Regarding 'log -v', the data below probably won't tell you anything you
> don't already know, but just in case:

>   ### Now try generating a log that has all the information I need to ###
>   ### start spot-checking this repository against the CVS record:     ###
> 
>   $ time bzr log --long -v > log-long-verbose.out
> 
>   ### Taking a very long time, more than half an hour so far. ###
>   ### There should be 94342 revisions, according to log.out.  ###
>   ###                                                         ###
>   ### At the rate it's going, I've calculated it will take    ###
>   ### abut a day and a half to complete.                      ###

Right. That's the reason why my benchmarks don't include log -v
across the whole branch yet, only for selected ranges. I went digging
last night and now understand better where the time is going. There's
no short term fix I can see. I'm optimistic that the split inventory
format ought to be able to greatly speed this up though.

Ian C.