Messages in this thread | | | Date | Wed, 20 Jun 2012 17:55:46 +0800 | From | Fengguang Wu <> | Subject | Re: [PATCH -mm] memcg: prevent from OOM with too many dirty pages |
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> > Finally, I wonder if there should be some timeout of that wait. I > > don't know why, but I wouldn't be surprised if we hit some glitch which > > causes us to add one! > > > > If we hit such a situation it means that flush is no longer working which > is interesting in itself. I guess one possibility where it can occur is > if we hit global dirty limits (or memcg dirty limits when they exist) > and the page is backed by NFS that is disconnected. That would stall here > potentially forever but it's already the case that a system that hits its > dirty limits with a disconnected NFS is in trouble and a timeout here will > not do much to help.
Agreed. I've run into such cases and cannot login even locally because the shell will be blocked trying to write even 1 byte at startup time. Any opened shells are also stalled on writing to .bash_history etc.
Thanks, Fengguang
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