Messages in this thread | | | Date | Tue, 27 Jun 2023 15:50:48 -0700 | Subject | Re: [GIT PULL] x86/misc for 6.5 | From | Arjan van de Ven <> |
| |
On 6/27/2023 3:43 PM, Linus Torvalds wrote: > On Tue, 27 Jun 2023 at 15:25, Linus Torvalds > <torvalds@linux-foundation.org> wrote: >> >> I don't know what the rules are - and some of the functions you test >> seem actively buggy (ie not handling alignment right etc). > > Oh. And you *only* test the 40-byte case. That seems a bit bogus. > > If I change the packet size from 40 to 1500, I get > > 02: 185.1 / 186.4 cycles (8b414316) Upcoming linux kernel version > 04: 184.9 / 186.5 cycles (8b414316) Specialized to size 40 > 06: 107.3 / 117.2 cycles (8b414316) New version > 22: 185.6 / 186.5 cycles (8b414316) Odd-alignment handling removed > > which seems unexpectedly bad for the other versions. >
I'm not surprised though; running 2 parallel streams (where one stream has a fixed zero as input, so can run OOO any time) .. can really have a performance change like this
| |