Benchmarks of kernel options to improve performance?

cyent · 09-05-2021, 04:24 PM

So there exists an improved version of the afl fuzzer....

https://github.com/AFLplusplus/AFLplusplus

...somewhere in that readme page is...

> Improve kernel performance: modify /etc/default/grub, set

GRUB_CMDLINE_LINUX_DEFAULT="ibpb=off ibrs=off kpti=off l1tf=off mds=off mitigations=off no_stf_barrier noibpb noibrs nopcid nopti nospec_store_bypass_disable nospectre_v1 nospectre_v2 pcid=off pti=off spec_store_bypass_disable=off spectre_v2=off stf_barrier=off";

then update-grub and reboot (warning: makes the system more insecure)

Anyone aware of any benchmarks on the effects of these on doing something like a large compilation and link?

ondoho · 09-07-2021, 10:51 PM

Quote:

Originally Posted by cyent

Anyone aware of any benchmarks on the effects of these on doing something like a large compilation and link?

Sorry, no.
You could start reading up on what they do at least, here: https://www.kernel.org/doc/html/late...arameters.html

zeebra · 09-08-2021, 03:49 AM

Quote:

Originally Posted by cyent

Anyone aware of any benchmarks on the effects of these on doing something like a large compilation and link?

You have to look in the kernel documentation. Some of those security features specifically mentions 5% or 7% performance penalty on doing X or Y. Easiest way is to look at the particular help entries in "make menuconfig".