Thanks. The BDI dirty limits sounds like a good idea. Is there already a patch for this, which I could try? I believe it works like this, Each BDI, will have a limit. If the dirty_thresh exceeds the limit, all the I/O on the block device will be synchronous. so, if I have sda & a NFS mount, the dirty limit can be different for each of them. I can set dirty limit for - sda to be 90% and - NFS mount to be 50%. So, if the dirty limit is greater than 50%, NFS does synchronously, but sda can work asynchronously, till dirty limit reaches 90%. Thanks --Chakri On 9/27/07, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote: > On Thu, 2007-09-27 at 23:50 -0700, Andrew Morton wrote: > > > What we _don't_ want to happen is for other processes which are writing to > > other, non-dead devices to get collaterally blocked. We have patches which > > might fix that queued for 2.6.24. Peter? > > Nasty problem, don't do that :-) > > But yeah, with per BDI dirty limits we get stuck at whatever ratio that > NFS server/mount (?) has - which could be 100%. Other processes will > then work almost synchronously against their BDIs but it should work. > > [ They will lower the NFS-BDI's ratio, but some fancy clipping code will > limit the other BDIs their dirty limit to not exceed the total limit. > And with all these NFS pages stuck, that will still be nothing. ] > > > > _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
