From: Luke Lu <git@vicaya.com>
Date: Fri, 07 Dec 2007 23:04:25 GMT
Subject: Re: Git and GCC
Message-ID: <B2B3D9E9-4A5C-4DE0-9FF9-B0F9304BDCD2@vicaya.com>
In-Reply-To: <m3hciutaoq.fsf@roke.D-201>

On Dec 7, 2007, at 2:14 PM, Jakub Narebski wrote:
> Giovanni Bajo <rasky@develer.com> writes:
>> On 12/7/2007 6:23 PM, Linus Torvalds wrote:
>>>> Is SHA a significant portion of the compute during these repacks?
>>>> I should run oprofile...
>>> SHA1 is almost totally insignificant on x86. It hardly shows up. But
>>> we have a good optimized version there.
>>> zlib tends to be a lot more noticeable (especially the
>>> *uncompression*: it may be faster than compression, but it's done  
>>> _so_
>>> much more that it totally dominates).
>>
>> Have you considered alternatives, like:
>> http://www.oberhumer.com/opensource/ucl/
>
> <quote>
>   As compared to LZO, the UCL algorithms achieve a better compression
>   ratio but *decompression* is a little bit slower. See below for some
>   rough timings.
> </quote>
>
> It is uncompression speed that is more important, because it is used
> much more often.

So why didn't we consider lzo then? It's much faster than zlib.

__Luke