Re: Using bitmaps to accelerate fetch and clone

From: David Michael Barr <b@rr-dav.id.au>
Date: Sep 27, 2012, 19:47 UTC
Message-ID: <CACPE+fsErzT3MyQdQj5XEvvMwnBam7LBU4XeNVZ+-zG+XYN0cA@mail.gmail.com>
In-Reply-To: <20120927172037.GB1547@sigill.intra.peff.net>

Hi all,

On Fri, Sep 28, 2012 at 3:20 AM, Jeff King <peff@peff.net> wrote:

Show 15 quoted lines

> On Thu, Sep 27, 2012 at 07:17:42PM +0700, Nguyen Thai Ngoc Duy wrote:
>
>> > Operation                   Index V2               Index VE003
>> > Clone                       37530ms (524.06 MiB)     82ms (524.06 MiB)
>> > Fetch (1 commit back)          75ms                 107ms
>> > Fetch (10 commits back)       456ms (269.51 KiB)    341ms (265.19 KiB)
>> > Fetch (100 commits back)      449ms (269.91 KiB)    337ms (267.28 KiB)
>> > Fetch (1000 commits back)    2229ms ( 14.75 MiB)    189ms ( 14.42 MiB)
>> > Fetch (10000 commits back)   2177ms ( 16.30 MiB)    254ms ( 15.88 MiB)
>> > Fetch (100000 commits back) 14340ms (185.83 MiB)   1655ms (189.39 MiB)
>>
>> Beautiful. And curious, why do 100->1000 and 10000->10000 have such
>> big leaps in time (V2)?
>
> Agreed. I'm very excited about these numbers.

+1

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>> Definitely :-). I have shown my interest in this topic before. So I
>> should probably say that I'm going to work on this on C Git, but
>> sllloooowwwly. As this benefits the server side greatly, perhaps a
>> GitHubber ;-) might want to work on this on C Git, for GitHub itself
>> of course, and, as a side effect, make the rest of us happy?
>
> Yeah, GitHub is definitely interested in this. I may take a shot at it,
> but I know David Barr (cc'd) is also interested in such things.

Yeah, I'm definitely interested, I love this stuff.

-- David Michael Barr