[gmx-users] low latency

[Carsten Kutzner]

On Jan 13, 2009, at 9:15 PM, ha salem wrote:

> Dear Karsten and gromacs specialists
> I enabled flow control on hp procurve now I want to know how I can  
> config low latency on the network ?is it required?
> thank you
There are quite some parameters that affect Ethernet performance. They  
can
be found in the /proc/net/ filesystem, where exactly will depend on  
your type of
system. These settings can also be changed with programs like e.g.  
"ethtool".

Did your performance get better with flow control? I would not look at  
the CPU
usage % but perform a benchmark on 1, 2, 4, ... CPUs and compare the  
ns/day
numbers before and after you make changes. These numbers are far more
reliable because a high CPU usage % does not necessarily mean you have  
good
scaling. You could also compare the md.log files to find out which  
parts of
mdrun eat up most of the time.

Carsten