Hi, I am trying to track down a performance drop with the ASPEED xorg video driver between FreeBSD 11 and 12 (I'm not expecting miracles from it but it was basically unusable..)
I wondered if some of the speculative execution mitigations could be causing the problem so I did some digging and found these.. vm.pmap.pti="0" # Disable page table isolation hw.ibrs_disable="1" # Disable Indirect Branch Restricted Speculation hw.mds_disable="0" # Disable Microarchitectural Data Sampling flush hw.vmm.vmx="1" # Don't flush RSB on vmexit (presumably only affects bhyve etc) hw.lazy_fpu_switch="1" # Lazily flush FPU Does anyone know of any others? I have 2 systems with the same motherboard (Supermicro X11SSH-F), one is older and runs FreeBSD 11 (and had an older BIOS_ and the newer runs FreeBSD 12. FWIW on FreeBSD 11 the performance (measured by a subset of x11perf benchmarks) went down 40% after updating to the latest BIOS (2.2a). Unfortunately on FreeBSD 12 rolling back to the original BIOS (2.2) did not improve performance. -- Daniel O'Connor "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum _______________________________________________ freebsd-stable@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
