maybe it will be fixed in kernel 3.9 http://www.phoronix.com/scan.php?page=news_item&px=MTMxNzA
2013/3/11 Florian Philipp <li...@binarywings.net> > Am 10.03.2013 13:48, schrieb Florian Philipp: > > Am 10.03.2013 00:53, schrieb cosmoslx lin:> > >> 2013/3/10 Volker Armin Hemmann <volkerar...@googlemail.com > >> <mailto:volkerar...@googlemail.com>> > >> > >> Am 09.03.2013 19:15, schrieb Florian Philipp: > >> > Hi list! > >> > > >> > Whenever I do sequential IO for a long stretch of time (e.g. > >> md5summing > >> > 40 GB), I'm experiencing high load (ca. 6 on a 4 CPU system) and > >> > temporary freezes of most applications. For example, switching > between > >> > tabs in konsole sometimes takes more than 2 seconds. > >> > > > [...] > >> > > >> congratulation. You hit 'the bug'. Been around for ages, but for > magical > >> reasons kernel dev are unable to see or unable to do something > about it. > >> If you are using a vanilla kernel, posting on lkml might be the > right > >> thing to do. > >> > >> I have try the BFQ patch outside of the kernel mainline, it works well. > >> Maybe you would like to see: > >> http://algo.ing.unimo.it/people/paolo/disk_sched/ > >> > > > > Thanks. I'll try pf-sources which should to include that patch set. > > > > Regards, > > Florian Philipp > > > > pf-sources (only BFQ enabled, not BFS) helped somewhat. kswapd still > likes to keep one CPU busy when IO is happening but I suspect cleancache > to be the culprit for that. I'll test without it later. > > Regards, > Florian Philipp > > > -- Best regards! ------------------------------------------------ Yu-yu Lin(林育宇) The Guangdong Key Laboratory of Information Security Technology (IST), School of Information Science and Technology, Sun Yat-sen (Zhongshan) University (中山大学), Guangzhou,P.R.China. Email: cosmo...@gmail.com ------------------------------------------------ <cosmo...@gmail.com>
