Re: [PATCH v3] refs: Use binary search to lookup refs faster

From: Julian Phillips <julian@quantumfyre.co.uk>
Date: Sep 30, 2011, 08:04 UTC
Message-ID: <a9f3dba5f48adfa603d76b7d49111e3d@quantumfyre.co.uk>
In-Reply-To: <7vwrcqpuc7.fsf@alter.siamese.dyndns.org>

On Thu, 29 Sep 2011 20:44:40 -0700, Junio C Hamano wrote:

Show 19 quoted lines

> Martin Fick <mfick@codeaurora.org> writes:
>
>> This works for me, however unfortunately, I cannot find any
>> scenarios where it improves anything over the previous fix
>> by René.  :(
>
> Nevertheless, I would appreciate it if you can try this _without_ 
> René's
> patch. This attempts to make resolve_ref() cheap for _any_ caller. 
> René's
> patch avoids calling it in one specific callchain.
>
> They address different issues. René's patch is probably an 
> independently
> good change (I haven't thought about the interactions with the topics 
> in
> flight and its implications on the future direction), but would not 
> help
> other/new callers that make many calls to resolve_ref().

It certainly helps with my test repo (~140k refs, of which ~40k are branches). User times for checkout starting from an orphaned commit are:

No fix          : ~16m8s
+ Binary Search : ~4s
+ René's patch  : ~2s

(The 2s includes both patches, though the timing is the same for René's patch alone)

-- 
Julian