The courseware for my Linux Kernel Fundamentals course is now available from ITcourseware at http://bit.ly/bf82sN.

After hours of searching the Web, I have found nothing that really sheds a whole lot of light on the subject of tuning CFS. Most of the pages on the Web refer to CFS as it was in version 2.6.23 of the Linux kernel. Most web pages do not provide accurate information. I really wonder about the system administrator who could not  understand why he was unable create a directory or file in the /proc directory. While I do not know the the best set of values for the tuneable parameters, I can, hopefully,  shed some light on the subject. » Continue reading “Tuning the Linux Kernel’s Completely Fair Scheduler”

The Linux Kernel manages all hardware through device drivers. Furthermore, the kernel operates in its own protected memory space, which is not accessible from user memory space. Hardware device communicate to the Kernel via interrupts and exceptions. User applications communicate to the Kernel via system calls, which actually trigger a CPU exception that interrupts the Kernel. The question becomes, how can we access what the Kernel knows about the hardware from a user space application? What user applications allow us to view this information? » Continue reading “Hardware Management and Linux”