[Coin-discuss] clp performance much worse with g++4.1 vs. g++4.0

[Stuart A Siegel]

After John mentioned that he doesn't see a difference I dug a bit deeper. 
It turns out that the compiler issue is a red herring, my aplogies. What's 
causing the performance difference is my (apparently) incorrect build 
procedure.

When I build just Clp (using ../Clp-1.6.0 prefix=[somedirectory] && make 
install) then performance is good from somedirectory/bin/clp

If I build Clp, Osi-0.97.0, and then Cbc-2.0.0 in that order using the 
**same** prefix then somedirectory/bin/clp performs three times worse than 
when I only build Clp.  This result is independent of the g++ version 
being used.  I chose to build this way (all three into the same install 
directory) because I had assumed that each provides a unique set of shared 
objects, but my experience suggests that  this is not the case. 

John, I'll be at Watson tomorrow (in fact, I think I'm across the hall 
from you) so I can show you what I mean.  I will post the mps file on my 
gsa account and send you a link in separate message.

-----------------------------------------------------------------------------------------
Stuart Siegel - IBM TJ Watson Laboratory 33-238
(M) 914.396.9506 (H) 973.379.1810 (O) 914.945.1674
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/coin-discuss/attachments/20071209/bd1f2579/attachment.html>