loggerhead vs packs performance

[Michael Hudson]

On 26 Sep 2007, at 22:17, Robert Collins wrote:

> On Wed, 2007-09-26 at 17:42 +0100, Michael Hudson wrote:
>> Robert asked me to do check loggerhead's performance when pointed at
>> a repository using packs (I tested with was bzr.dev).
>>
>> The performance is summarized in this table (the numbers are the
>> minimum page load time in ms reported by 'ab -n 15' on the given  
>> view):
>
>> (this was done on my old slow os x powerbook, which is why the
>> numbers are SO uniformly bad).
>>
>> For the changelog and inventory views, packs are a little slower, but
>> probably nothing some tuning and effort wouldn't sort out.  Annotate
>> is pretty slow (but that may have been expected?
>
> Yes, because annotate loads text indices.
>
>>  And the rendering
>> performance is still dreadful here).  The revision view, though, is
>> atrociously slow with packs, and this is borne out with timings of
>> 'bzr diff':
>
> Diff, like annotate, accesses the text indices; these currently (like
> knits) load the entire index, never a partial index, but unlike  
> bzr.dev
> there is one for the whole tree, not one per file.

Ah ha.  That makes sense.

> So, no massive surprises here for me, its good to know that it's not
> slow in a suprising way.

Indeed.

Cheers,
mwh