Messages in this thread | | | Date | Mon, 12 Sep 2005 18:23:28 +0530 | From | Bharata B Rao <> | Subject | Re: VM balancing issues on 2.6.13: dentry cache not getting shrunk enough |
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On Sun, Sep 11, 2005 at 11:16:30PM -0700, Martin J. Bligh wrote: > > > --Theodore Ts'o <tytso@mit.edu> wrote (on Sunday, September 11, 2005 23:16:36 -0400): > > > On Sun, Sep 11, 2005 at 05:30:46PM +0530, Dipankar Sarma wrote: > >> Do you have the /proc/sys/fs/dentry-state output when such lowmem > >> shortage happens ? > > > > Not yet, but the situation occurs on my laptop about 2 or 3 times > > (when I'm not travelling and so it doesn't get rebooted). So > > reproducing it isn't utterly trivial, but it's does happen often > > enough that it should be possible to get the necessary data. > > > >> This is a problem that Bharata has been investigating at the moment. > >> But he hasn't seen anything that can't be cured by a small memory > >> pressure - IOW, dentries do get freed under memory pressure. So > >> your case might be very useful. Bharata is maintaing an instrumentation > >> patch to collect more information and an alternative dentry aging patch > >> (using rbtree). Perhaps you could try with those. > > > > Send it to me, and I'd be happy to try either the instrumentation > > patch or the dentry aging patch. > > Other thing that might be helpful is to shove a printk in prune_dcache > so we can see when it's getting called, and how successful it is, if the > more sophisticated stuff doesn't help ;-) >
I have incorporated this in the dcache stats patch I have. I will post it tommorrow after adding some more instrumentation data (number of inuse and free dentries in lru list) and after a bit of cleanup and testing.
Regards, Bharata. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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