Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-06 Thread Alexey Shvetsov
Also for additional performance benefit you can use atlas math library and compile gromacs and fftw with additional cflags like '-mfpmath=sse - m' This will enable sse math (by default gcc generates i386 and sse). PS Also you can use CFLAGS="-O2 -pipe -march=native -mfpmath=sse - m' PPS also on l

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Szilárd Páll
Additionally, if you care about a few percent extra performance, you should use gcc 4.5 or 4.6 for compiling Gromacs as well as FFTW (unless you have a bleeding-edge OS which was built with any of these latest gcc versions). While you might not see a lot of improvement in mdrun performance (wrt gcc

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Mark Abraham
On 6/07/2011 1:36 AM, Anthony Cruz Balberdi wrote: Thank you very much Mark. Another question, will be better if I compile FFTW than use the one included in my linux distro? Per the GROMACS installation instructions, you want the precision of FFTW to match the precision of GROMACS. You'll have

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Anthony Cruz Balberdi
Thank you very much Mark. Another question, will be better if I compile FFTW than use the one included in my linux distro? Anthony On Tue, Jul 5, 2011 at 11:08 AM, Mark Abraham wrote: > On 6/07/2011 12:28 AM, Matthew Zwier wrote: > >> Sorry about that. >> >> The default options are nearly optima

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Mark Abraham
On 6/07/2011 12:28 AM, Matthew Zwier wrote: Sorry about that. The default options are nearly optimal, and the difference between a modern (4.4 or 4.5) series GCC and the Intel compilers are only a couple of percent. Just be sure to have FFTW available. ... if planning to use PME. Also, Intel

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Matthew Zwier
Sorry about that. The default options are nearly optimal, and the difference between a modern (4.4 or 4.5) series GCC and the Intel compilers are only a couple of percent. Just be sure to have FFTW available. On Tue, Jul 5, 2011 at 10:26 AM, Matthew Zwier wrote: > Hi Anthony, > > The default op

Re: [gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Matthew Zwier
Hi Anthony, The default options are nearly optimal, and the difference between a modern (4.4 or 4.5) GCC On Tue, Jul 5, 2011 at 10:01 AM, Anthony Cruz Balberdi wrote: > Dear Users: > > We recently received our new computer.  This computer have 4 multicore > Opteron AMD cpus and I am planning to

[gmx-users] Gromacs compilation on AMD multicore

2011-07-05 Thread Anthony Cruz Balberdi
Dear Users: We recently received our new computer. This computer have 4 multicore Opteron AMD cpus and I am planning to install GROMAS. Which options I will need to use in order to achieve the best possible performance? Which compiler GNU or Intel? Thank you for all you help. Anthony -- gmx-us