From: Linus Torvalds <torvalds@osdl.org>
Date: Fri, 22 Apr 2005 15:31:55 GMT
Subject: Re: Mozilla SHA1 implementation
Message-ID: <Pine.LNX.4.58.0504220824480.2344@ppc970.osdl.org>
In-Reply-To: <17000.43340.760901.175004@cargo.ozlabs.ibm.com>



On Fri, 22 Apr 2005, Paul Mackerras wrote:
> Linus Torvalds writes:
> 
> > Interestingly, the Mozilla SHA1 code is about twice as fast as the openssl
> > code on my G5, and judging by the disassembly, it's because it's much
> > simpler. I think the openssl people have unrolled all the loops totally,
> > which tends to be a disaster on any half-way modern CPU. But hey, it could
> > be something as simple as optimization flags too.
> 
> Which gcc version are you using?

gcc-3.3.3.

But it's more likely the precompiled libssl. I'm not compiling the openssl
thing myself, but just using the standard 0.9.7a version that comes with
YDL. Which, btw, causes all of 

	/lib/libcrypto.so.4
	/usr/lib/libgssapi_krb5.so.2
	/usr/lib/libkrb5.so.3
	/lib/libcom_err.so.2
	/usr/lib/libk5crypto.so.3
	/lib/libresolv.so.2
	/lib/libdl.so.2

to also be included. Oh, well.

> I get the opposite result on my 2GHz G5: the Mozilla version does
> 45MB/s, the openssl version does 135MB/s, and my version does 218MB/s.
> The time for a fsck-cache on a linux-2.6 tree (cache hot) is 8.0
> seconds for the Mozilla version, 5.2 seconds for the openssl version,
> and 4.4 seconds for my version.

I get 16 seconds for the openssl one, and 8 for the Mozilla one. I'll try 
your version.

		Linus