Re: gcc 2.95 vs 3.21 performance

From: Denis Vlasenko (vda@port.imtp.ilyichevsk.odessa.ua)
Date: Wed Feb 05 2003 - 06:41:34 EST


On 5 February 2003 12:36, Andreas Schwab wrote:
> Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> writes:
> |> I am damn sure that if you compile with less sadistic alignment
> |> you will get smaller *and* faster kernel.
>
> So why don't you try it out? GCC offers everything you need for this
> experiment.

I did. Others did it too on occasion.

My argument was against overusing optimization techniques.
You cannot speed up kernel by aligning *everything* to 32 bytes,
or by unrolling all loops, or by aggressive inlining.
That's too easy to work. You get kernel which is bigger
*and* slower.

--
vda
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