Problems
From BenchIT-Wiki
There may be some platform specific problems in running BenchIT measurements. Heres a list of common problems and how they can be solved.
Contents |
Error while starting batch jobs
Error while loading environment file *_env: It may be, that your shell isn't POSIX compliant
- on bash and IRIX64 be sure, that the environment variable _XPG=1 is set. (The best solution is write export _XPG=1 in your .bashrc)
- on other systems, which have csh or other non POSIX compliant shells as /bin/sh, try the script change_sh.sh (in the benchit root folder). If you're using the GUI under Linux and have a bash on your system and on the remote system, you may start this script on your computer.
Error while linking FORTRAN
On some systems a mixed C/FORTRAN program better uses the FORTRAN compiler for linking. Change the link command in the Compile.SH and try it again
On some systems, the number of _s, which is added to FORTRAN routines differs from our default. There may be a compiler option to change this.
Powersave-Systems
Many modern CPU's try to minimize their energy-footprint. Therefor they lower the clock rate of the cpu if the system is idle. The deamon watching the system for activity needs (several hundred) cycles to recognize load on the system before switching back to full power. This behavior creates strange/wrong results while benchmarking.
The linux tool powersave can be set to maximum with the option "-f". Simply add the following to your .bashrc to set the machine to max:
##############################
# set cpu to max performance #
##############################
if [ ! "PERFORMANCE" == `powersave -c` ]; then powersave -f; fi
However, powersave may not have come with your system, so either install it, if you can, or try switching the cpufreq-governor of modern linux kernels:
on GNOME-based distributions, you can alter the gconf keys using gconftool:
gconftool -s --type string /apps/gnome-power-manager/cpufreq/policy_ac performance
or
gconftool -s --type string /apps/gnome-power-manager/cpufreq_ac_policy performance
If you have not setup any desktop environment, but you have root privileges (direct, or via su/sudo), you can try:
echo performance | tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
while beeing root, to switch the governor for the selected cpu.
For further help and information, please consider your distributions (in)-official documentations.
Loading of C-Timer for JAVA under AMD64
In some cases, the C timer for JAVA kernels won't be found on AMD64 systems. This can result from different ELF-formats. If your Java Runtime Environment is compiled for 32 bit, it won't load the compiled 64 bit libraries. Make sure, that the JAVA ELF and the library ELF are the same.
When everything fails
- Get a cup of coffee
- calm down ( you can also smoke ;) )
- watch a vid http://www.youtube.com/watch?v=gg5_mlQOsUQ&feature=related
