Messages in this thread |  | | | Date | Fri, 7 Jul 2000 20:00:31 -0700 | | From | Chip Salzenberg <> | | Subject | 2.2.17pre10 pauses fixed by Andrea's VM-global-patch-1 |
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While running the "brutal" (-- Alan Cox) Cerberus test suite on a 2.2.17pre10 kernel, we've been seeing pauses of from five to twenty seconds every two minutes or so. As best I can tell from SysReq, when the kernel pauses, it's spending time in shrink_mmap(). When pauses occur, free RAM is down to about 1M; but it's not a true OOM, since there's always lots of free swap space. (Cerberus scales its memory usage to avoid filling swap.)
Good News: The pauses are *almost* completely gone after applying Andrea's patch entitled "VM-global-patch-1". The kernel still pauses, but only very occasionally, and for no more than two to four seconds; and even during the pauses, interactive performance is reasonable. According to Jason Collins, creator of Cerberus, it's at least as good as any previous 2.2.x when subjected to a Cerberus attack.
Thanks, Andrea!
PS: Anyone who wants to stress the VM, I recommend trying Cerberus as part of your testing mix. Get it from SourceForge: <URL:https://sourceforge.net/projects/va-ctcs/>
Testing Details: Kernel: 2.2.17pre10 Config: SMP, 2G, NFS root Hardware: Intel Lancewood, two P3s, 512M RAM, DAC960 RAID Relevant Patches: Dave/Trond/Neil's NFS merge Andrea's VM-global-patch-1 Andrea's BIGMEM Solar Designer's security Probably Irrelevant Patches: Rik's fair share scheduler (but disabled at the time) Andre Hedrick's IDE Mingo's RAID VA's E820 memory probe Backport of 2.4's AGP driver
-- Chip Salzenberg - a.k.a. - <chip@valinux.com> "I wanted to play hopscotch with the impenetrable mystery of existence, but he stepped in a wormhole and had to go in early." // MST3K - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
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