PATCH: ldconfig.c considers ld.so.conf entries before /lib,/usr/lib

[Jakub Jelinek]

On Wed, Aug 29, 2001 at 10:26:25PM -0500, Dirk Eddelbuettel wrote:
> III. Illustration of Atlas' benfits
> 
> This shows some echo'ed code for R and Octave (doing simple matrix cross
> products) along with timings in seconds. 
> 
> Evaluating Atlas libs at /usr/lib/atlas on size 1500
>  
> GNU R: m<-matrix(rnorm(1500*1500),ncol=1500); cat(system.time(crossprod(m))[1])
>   Without Atlas: 92.66
>   With Atlas   : 9.5
>  
> GNU Octave: X=randn(1500,1500); t=cputime(); Y=X'*X; disp(cputime-t)
>   Without Atlas: 96.100
>   With Atlas   : 9.8200
> 
> Evaluating Atlas libs at /usr/lib/3dnow/atlas on size 1500
>  
> GNU R: m<-matrix(rnorm(1500*1500),ncol=1500); cat(system.time(crossprod(m))[1])
>   Without Atlas: 92.7
>   With Atlas   : 7.86
>  
> GNU Octave: X=randn(1500,1500); t=cputime(); Y=X'*X; disp(cputime-t)
>   Without Atlas: 96.060
>   With Atlas   : 8.1900

If libblas.so from Atlas is that much better, I don't see the point why you
just don't package it up separately as standard libblas.so.

Also, if you place it under say /usr/lib/`uname -m`/libblas.so, ldconfig
will pick it up in the cache as architecture optimized and thus ld.so will
pick it up preferably to /usr/lib/libblas.so.

	Jakub