Language Selection

English French German Italian Portuguese Spanish

Linux: Tuning CFS

Filed under
Linux

Nick Piggin used 'git bisect' to track a lmbench regression to the main CFS commit, leading to an interesting discussion between Nick and Ingo Molnar. Ultimately the regression was tracked down to the temporary configurability of the scheduler while it is tuned for optimal performance, "one reason for the extra overhead is the current tunability of CFS, but that is not fundamental, it's caused by the many knobs that CFS has at the moment." The solution, already coded but not yet merged in the mainline kernel "changes those knobs to constants, allowing the compiler to optimize the math better and reduce code size," and as a result result, "CFS can be faster at micro-context-switching than 2.6.22."

Ingo described the lmbench configuration in question as a "micro-benchmark", and noted that with a macro-benchmark better performance was more pronounced, "because with CFS the _quality_ of scheduling decisions has increased.

More Here




More in Tux Machines

Security: Trezor, Kaspersky and Secure [sic] Enclave Processor

Android Leftovers

Linux-loving lecturer 'lost' email, was actually confused by Outlook

ON-CALL Friday means a few things at El Reg: a new BOFH. A couple of beers. And another instalment of On-Call, our weekly column in which we take reader-contributed tales of being asked to do horrible things for horrible people, scrub them up and hope you click. This week, meet “Newt” who a dozen or more years ago worked at a College that “decided to migrate from a Linux system to Microsoft Outlook with an Exchange back end.” Read more

Looks Like Debian GNU/Linux Runs on Quite a Few Mobile Devices, Including Pyra

Debian Project's W. Martin Borgert reports today that work on making the famous and widely-used Debian GNU/Linux operating system run on various mobile devices continues these days. Read more