QLogic OFED+ Host Software User Guide, Rev. B

3–TrueScale Cluster Setup and Administration
Host Environment Setup for MPI
• smartd
• readahead
The service comprising the TrueScale driver and SMA is:
• openibd
Other services may be required by your batch queuing system or user community.
If your system is running the daemon irqbalance, QLogic recommends turning it
off. Disabling irqbalance will enable more consistent performance with programs
that use interrupts. Use this command:
# /sbin/chkconfig irqbalance off
See “Erratic Performance” on page F-9 for more information.
Disable Powersaving Features
Hyper-Threading
If you are running benchmarks or large numbers of short jobs, it is beneficial to
disable the powersaving features, since these features may be slow to respond to
changes in system load.
For RHEL4 and RHEL5, run this command as a root user:
# /sbin/chkconfig --level 12345 cpuspeed off
For SLES 10 and SLES 11, run this command as a root user:
# /sbin/chkconfig --level 12345 powersaved off
After running either of these commands, reboot the system for the changes to
take effect.
If you are using Intel NetBurst ® Processors that support Hyper-Threading, QLogic
recommends turning off Hyper-Threading in the BIOS, which will provide more
consistent performance. You can check and adjust this setting using the BIOS
Setup utility. For specific instructions, follow the hardware documentation that
came with your system.
Host Environment Setup for MPI
After the QLogic OFED+ Host software and the GNU (GCC) compilers have been
installed on all the nodes, the host environment can be set up for running MPI
programs.
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