Archive for April, 2010

Disable CPU frequency scaling

April 30, 2010

The CPU frequency scaling drove me crazy. My slow fanless z520 based system slowed down a lot using the ondemand mode. It just meets my needs when I set it to  performance mode, but on every re-boot the system fell back to ondemand mode.  The annoying thing is that I can not disable the CPU scaling anywhere. The solution has been explained in  http://ubuntuforums.org/showthread.php?p=9159702

The solution is to configure the performance mode persistently, just  add the following lines to /etc/rc.local, per CPU one line:

echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor

Binary Scanner (beta)

April 1, 2010

Binary Scanner is a frontend for ldd and nm to view and analyze symbol names of dynamicaly linked ELF executables, as they are used by Linux and other Unix like operating systems.

The tool shall help developers and release managers to improve the quality of binaries shipped with Linux releases, in terms of number of library dependencies and vast amount of dynamic symbols within the libraries and executables.

As it seems, some executables depend on shared libraries such as libm.so but do not refer to any of its functions or constants. More over, many executables re-export symbols  which are have been “cloned” from library header files accidentely. Both influence the startup time of dynamicly linked executables significantly.

This tool gives developers and Q&A an easy to use tool at hand to inspect and analyze selected executables.

The sources are hosted at http://sourceforge.net/projects/binscan/ The tool provides a text mode and a Gtk+ based GUI mode.