News: 0001598179

  ARM Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life (Terry Pratchett, Jingo)

Turbostat Introduces New Cache Statistics, Nova Lake + Wildcat Lake Support

([Linux Kernel] 12 Hours Ago Linux 6.19 Turbostat)


Turbostat is the Linux command-line utility for reporting CPU frequency / power / C-states and related performance / power management items namely for modern AMD and Intel processors. This CLI utility lives within the Linux kernel source tree and for Linux 6.19 has picked up a few new features.

Turbostat in Linux 6.19 adds some new last level cache (LLC) statistics of: Last Level Cache Thousands of References Per Second "LLCkRPS" and Last Level Cache Hit % "LLC%hit". These LLC cache statistic reporting features were added by Intel.

As for the new LLCkRPS metric, the updated documentation explains:

"For CPUs with an L3 LLC, this is the number of references that CPU made to the L3 (and the number of misses that CPU made to it's L2). For CPUs with an L2 LLC, this is the number of references to the L2 (and the number of misses to the CPU's L1). The system summary row shows the sum for all CPUs. In both cases, the value displayed is the actual value divided by 1000 in the interest of usually fitting into 8 columns."

In addition to these new CPU cache statistics, Turbostat now also recognizes the upcoming Intel Wildcat Lake and Nova Lake platforms. Plus there are new checks for usage on VMware and AWS environments as well as adding an MSR check for Android usage. See [1]this merge for all the Turbostat changes in Linux 6.19.



[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=10003ff8ce7273d1fe045d63d1a5c9d979e3d47e


Alan Cox Releases Quantum Kernel
Submitted by Dave Finton

A surprising development in the linux-kernel mailing list surfaced when
Alan Cox announced the release of a 2.2 Linux kernel existing both as an
official stable kernel and as a prepatch kernel. This immediately spurred
the creation of two different realities (and hence two different Alan
Coxes), where a kernel would not settle down to one or the other state
until someone looked at it.

"I think this resulted from the large number of 'final' prepatch kernels
prior to the 2.2.14 release," said David Miller, kernel networking guru
and gas station attendent (he'll settle down to one or the other state
when someone looks at him).

When word of this development spread to Microsoft, Bill Gates was
extremely delighted. The Redmond, WA campus has been plagued with quantum
fluctuations ever since the inception of Windows 2000 back in 1992. "Our
release date has been existing in infinitely many states since the very
beginning," said a Microsoft spokesperson. "This just shows the Linux
operating system cannot scale to multiple realities as well as our OS."