[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: [RFD] optimized versions of openssl

"Vince Mulhollon" <vlm@norlight.com> writes:

> On 09/04/2002 08:51:02 AM ilmari@ping.uio.no (Dagfinn Ilmari Mannsåker)
> wrote:
> >> division and multiplication. Recompiling libssl with SPARCv8
> >> optimizations speeds up logging in with ssh on an Ultra1 (SPARCv9) by
> >> a factor of 6, IIRC. See the debian-sparc archives for details.
> This is quite possibly the first time during the eternal debate of
> processor specific optimizations on debian-devel, that someone has ever
> posted real measured numbers, showing greater than single digit percentage
> improvements for optimization.  That changes the debate.
> In this individual case, I'd agree with you, it would be a great idea for
> someone to create a libssl-*-sparc8 package.

Compiling with "-Os -mcpu=ev56" on alpha saves 10-30% on space and due
to less cache misses it generally speeds up things or does not
hurt. The -mcpu flag avoids emulation of byte accesses that can realy
hurt performance.

But for cases like this where a general optimisation uses more
advanced cpu features I think the right way to go is to compile
everything locally or a subset of packages that benefit from it. There
is apt-src and apt-build and at some time there will be sourcerer to
aid you with such an undertaking.


Reply to: