[Symphony] Dramatic performance drop since 5.1.10

[Ashutosh Mahajan]

Dear Pierre Le Bodic

could you please send some of the MPS files. i will take a look.

On Thu, 10 Sep 2009, Pierre.Lebodic at lri.fr wrote:

> Hello,
> 
> I've been using the C callbacks of Symphony 5.1.10 for a while and I
> recently tried updating to 5.2. On a batch of 80 test instances, I
> measured the run time of the updated solver. "Sys time" went from 2sec
> with 5.1 to 2m55sec with 5.2. As a comparison, cbc 2.3 takes 23sec. A
> little digging made me try with feasibility pump disabled, which roughly
> cut the sys time in two, but it's still nowhere close the previous
> version. I'd like to know if there are parameters that can be changed to
> get closer to how fast Symphony 5.1 performs. I'm solving 0-1 problems. I
> can provide MPS files if needed.
> 
> The reason why I'm willing to switch to 5.2 is that I'm experiencing what
> seems to be a bug: when TM_gap_limit != -1, feasible solutions that don't
> respect the gap limit are produced. As far as I've been able to see, this
> bug seems to be fixed in 5.2. If you know about this bug, a quick edit in
> my 5.1 source would also do the trick.
> Thanks in advance
> 
> Pierre Le Bodic
> 
> _______________________________________________
> Symphony mailing list
> Symphony at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/symphony

--
regards
Ashutosh Mahajan
http://coral.ie.lehigh.edu/~asm4