Re: Performance Benchmark for PTI (aka Meltdown mitigation)
On Mon, Mar 12, 2018 at 04:36:05PM -0400, Arshan Khanifar wrote: > I did some benchmarking for the two revisions: > results are here: > https://github.com/ArshanKhanifar/pti-benchmark/tree/master/stable-11-pre-after/results > first file is before pti patch and second file is after pti patch. 10x! .2 is is before pti patch and .4 is after pti patch? This is like pti patch (w/ pti off) do small speed up (about 1%)? > On Fri, Mar 9, 2018 at 10:16 AM, Slawa Olhovchenkov wrote: > > > On Fri, Mar 09, 2018 at 09:58:55AM -0500, Ed Maste wrote: > > > > > On 9 March 2018 at 07:01, Slawa Olhovchenkov wrote: > > > > On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote: > > > > > > > >> Executive Summary: > > > >> - The PTI feature increases the system call times by more than 100%. > > > >> - As a macrobenchmark, buildworld was used. Wall clock and user time > > > >> showed no statistically-significant changes, while system time > > > >> increased by less than 5%. > > > >> > > > >> This email contains the results for benchmarking the performance of > > the > > > >> PTI patch on FreeBSD 12-current. As a microbenchmark, timing of > > > >> getppid(2) system call was used, and as a macrobenchmark, a number of > > > >> buildworld tasks were timed. > > > >> > > > > > > > > Can you also run pre-patched kernel? > > > > > > It's not easy to do an apples-to-apples comparison as there were a few > > > followup changes to the PTI work, interspersed with unrelated changes. > > > That said, I think Arshan has some benchmarks obtained during the > > > development of the PTI changes that may be illustrative. > > > > > > The best approach is probably to compare stable/11 at r329450 (last > > > stable/11 revision before the merge) with r329462 with PTI and IBRS > > > disabled. > > > > Stable/11 more interesting to me, nice to see. > > > > ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: Performance Benchmark for PTI (aka Meltdown mitigation)
I did some benchmarking for the two revisions: results are here: https://github.com/ArshanKhanifar/pti-benchmark/tree/master/stable-11-pre-after/results first file is before pti patch and second file is after pti patch. On Fri, Mar 9, 2018 at 10:16 AM, Slawa Olhovchenkov wrote: > On Fri, Mar 09, 2018 at 09:58:55AM -0500, Ed Maste wrote: > > > On 9 March 2018 at 07:01, Slawa Olhovchenkov wrote: > > > On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote: > > > > > >> Executive Summary: > > >> - The PTI feature increases the system call times by more than 100%. > > >> - As a macrobenchmark, buildworld was used. Wall clock and user time > > >> showed no statistically-significant changes, while system time > > >> increased by less than 5%. > > >> > > >> This email contains the results for benchmarking the performance of > the > > >> PTI patch on FreeBSD 12-current. As a microbenchmark, timing of > > >> getppid(2) system call was used, and as a macrobenchmark, a number of > > >> buildworld tasks were timed. > > >> > > > > > > Can you also run pre-patched kernel? > > > > It's not easy to do an apples-to-apples comparison as there were a few > > followup changes to the PTI work, interspersed with unrelated changes. > > That said, I think Arshan has some benchmarks obtained during the > > development of the PTI changes that may be illustrative. > > > > The best approach is probably to compare stable/11 at r329450 (last > > stable/11 revision before the merge) with r329462 with PTI and IBRS > > disabled. > > Stable/11 more interesting to me, nice to see. > > ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: Performance Benchmark for PTI (aka Meltdown mitigation)
On Fri, Mar 09, 2018 at 09:58:55AM -0500, Ed Maste wrote: > On 9 March 2018 at 07:01, Slawa Olhovchenkov wrote: > > On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote: > > > >> Executive Summary: > >> - The PTI feature increases the system call times by more than 100%. > >> - As a macrobenchmark, buildworld was used. Wall clock and user time > >> showed no statistically-significant changes, while system time > >> increased by less than 5%. > >> > >> This email contains the results for benchmarking the performance of the > >> PTI patch on FreeBSD 12-current. As a microbenchmark, timing of > >> getppid(2) system call was used, and as a macrobenchmark, a number of > >> buildworld tasks were timed. > >> > > > > Can you also run pre-patched kernel? > > It's not easy to do an apples-to-apples comparison as there were a few > followup changes to the PTI work, interspersed with unrelated changes. > That said, I think Arshan has some benchmarks obtained during the > development of the PTI changes that may be illustrative. > > The best approach is probably to compare stable/11 at r329450 (last > stable/11 revision before the merge) with r329462 with PTI and IBRS > disabled. Stable/11 more interesting to me, nice to see. ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: Performance Benchmark for PTI (aka Meltdown mitigation)
On 9 March 2018 at 07:01, Slawa Olhovchenkov wrote: > On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote: > >> Executive Summary: >> - The PTI feature increases the system call times by more than 100%. >> - As a macrobenchmark, buildworld was used. Wall clock and user time >> showed no statistically-significant changes, while system time >> increased by less than 5%. >> >> This email contains the results for benchmarking the performance of the >> PTI patch on FreeBSD 12-current. As a microbenchmark, timing of >> getppid(2) system call was used, and as a macrobenchmark, a number of >> buildworld tasks were timed. >> > > Can you also run pre-patched kernel? It's not easy to do an apples-to-apples comparison as there were a few followup changes to the PTI work, interspersed with unrelated changes. That said, I think Arshan has some benchmarks obtained during the development of the PTI changes that may be illustrative. The best approach is probably to compare stable/11 at r329450 (last stable/11 revision before the merge) with r329462 with PTI and IBRS disabled. ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: Performance Benchmark for PTI (aka Meltdown mitigation)
On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote: > Executive Summary: > - The PTI feature increases the system call times by more than 100%. > - As a macrobenchmark, buildworld was used. Wall clock and user time > showed no statistically-significant changes, while system time > increased by less than 5%. > > This email contains the results for benchmarking the performance of the > PTI patch on FreeBSD 12-current. As a microbenchmark, timing of > getppid(2) system call was used, and as a macrobenchmark, a number of > buildworld tasks were timed. > Can you also run pre-patched kernel? ___ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
