| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20080430135035.b0b02533.kamezawa.hiroyu@jp.fujitsu.com> Date: Wed, 30 Apr 2008 13:50:35 +0900 From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com> To: "Ross Biro" <rossb@...gle.com> Cc: linux-mm@...ck.org, lkml <linux-kernel@...r.kernel.org>, "hugh@...itas.com" <hugh@...itas.com> Subject: Re: Page Faults slower in 2.6.25-rc9 than 2.6.23 On Tue, 29 Apr 2008 09:10:36 -0400 "Ross Biro" <rossb@...gle.com> wrote: > I don't know if this has been noticed before. I was benchmarking my > page table relocation code and I noticed that on 2.6.25-rc9 page > faults take 10% more time than on 2.6.22. This is using lmbench > running on an intel x86_64 system. The good news is that the page > table relocation code now only adds a 1.6% slow down to page faults. > It seems lmbench's pagefault program uses 'page fault by READ'. Then, this patch affects. (this patch was added at 2.6.24-rc?.) == http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=557ed1fa2620dc119adb86b34c614e152a629a80 == By it, ZERO_PAGE is not used for page fault in anonymous mapping. So it seems an expexted result. Thanks, -Kame > Ross > > 2.6.25-rc9: > > File & VM system latencies in microseconds - smaller is better > ------------------------------------------------------------------------------- > Host OS 0K File 10K File Mmap Prot Page 100fd > Create Delete Create Delete Latency Fault Fault selct > --------- ------------- ------ ------ ------ ------ ------- ----- ------- ----- > ipnn2 Linux 2.6.25- 13.9 7.6111 103.4 9.7453 926.0 0.711 2.14250 2.552 > ipnn2 Linux 2.6.25- 13.7 7.6243 310.7 9.6574 932.0 0.750 2.15970 2.555 > ipnn2 Linux 2.6.25- 13.9 7.6831 192.5 10.0 927.0 0.760 2.21310 2.553 > ipnn2 Linux 2.6.25- 13.9 7.5739 98.4 9.5330 927.0 0.703 2.17610 2.554 > ipnn2 Linux 2.6.25- 14.6 7.6429 39.1 10.8 935.0 0.763 2.17250 2.552 > ipnn2 Linux 2.6.25- 14.1 7.8777 129.8 9.9375 930.0 0.782 2.26460 2.559 > ipnn2 Linux 2.6.25- 14.8 7.9639 623.8 8.2042 927.0 0.773 2.21510 2.557 > ipnn2 Linux 2.6.25- 14.4 7.5842 622.3 8.3272 920.0 0.745 2.22210 2.558 > ipnn2 Linux 2.6.25- 14.2 7.6339 45.7 10.2 935.0 0.675 2.23860 2.554 > ipnn2 Linux 2.6.25- 14.1 7.7175 263.7 10.1 929.0 0.762 2.22350 2.556 > ipnn2 Linux 2.6.25- 13.9 8.1230 378.2 9.4343 975.0 0.752 2.25920 2.554 > > > 2.6.23: > File & VM system latencies in microseconds - smaller is better > ------------------------------------------------------------------------------- > Host OS 0K File 10K File Mmap Prot Page 100fd > Create Delete Create Delete Latency Fault Fault selct > --------- ------------- ------ ------ ------ ------ ------- ----- ------- ----- > ipnn2 Linux 2.6.23- 218.0 0.912 1.94010 2.626 > ipnn2 Linux 2.6.23- 219.0 1.095 1.96400 2.597 > ipnn2 Linux 2.6.23- 219.0 0.774 1.96640 2.603 > ipnn2 Linux 2.6.23- 221.0 0.946 1.99950 2.601 > ipnn2 Linux 2.6.23- 219.0 0.902 1.99160 2.733 > ipnn2 Linux 2.6.23- 217.0 0.904 2.04790 2.601 > ipnn2 Linux 2.6.23- 225.0 0.893 1.99620 2.600 > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@...ck.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@...ck.org"> email@...ck.org </a> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists