Subject: Re: *horrible* performance?
To: Peter Seebach <seebs@plethora.net>
From: Jason R Thorpe <thorpej@zembu.com>
List: port-alpha
Date: 06/26/2000 12:01:06
On Mon, Jun 26, 2000 at 01:49:05PM -0500, Peter Seebach wrote:

 > On my laptop, I get about 1:2 performance, e.g. 15 minutes to compress an
 > 8-minute track.
 > 
 > On my alpha, I get about 1:4.5 performance, e.g., 28 minutes to compress an
 > 8-minute track.
 > 
 > The laptop:  PII-233, probably a "mobile" pentium II of some sort.  96MB of
 > SDRAM.
 > 
 > The alpha:  PC164-500, 256MB of memory, using all 8 SIMM slots.
 > 
 > The alpha otherwise runs probably 2x the speed of the laptop.
 > 
 > Both are using IDE disks.  The alpha was compiled with -O4, various options
 > suggested by the Makefile, -DFLOAT=double (stolen from our patches directory
 > in pkgsrc for lame 3.50), and -Mcpu=21164a -Wa,-m21164a or whatever that was
 > to tell it it's on a 21164a.
 > 
 > The laptop is 1.4ZD, the alpha is 1.4ZD.
 > 
 > This can't be right.  :)

Sure it can -- gcc (at least the version we're using right now) emits
terrible floating point code for the Alpha.

If someone wants to write an assembly version of libm for the Alpha, be
my guest.

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>