From: Linus Torvalds <torvalds@osdl.org>
Date: Mon, 03 Jul 2006 23:02:39 GMT
Subject: Re: Compression speed for large files
Message-ID: <Pine.LNX.4.64.0607031556480.12404@g5.osdl.org>
In-Reply-To: <44A99961.8090504@fys.uio.no>



On Tue, 4 Jul 2006, Joachim Berdal Haga wrote:
> 
> Here's a test with "time gzip -[169] -c file >/dev/null". Random data
> from /dev/urandom, kernel headers are concatenation of *.h in kernel
> sources. All times in seconds, on my puny home computer (1GHz Via Nehemiah)

That "Via Nehemiah" is probably a big part of it.

I think the VIA Nehemiah just has a 64kB L2 cache, and I bet performance 
plummets if the tables end up being used past that. 

And I think a large part of the higher compressions is that they allow the 
compression window and tables to grow bigger.

		Linus