From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Chinner Subject: Re: NFS page states & writeback Date: Sat, 26 Mar 2011 10:04:50 +1100 Message-ID: <20110325230450.GR26611@dastard> References: <20110325012803.GA25052@quack.suse.cz> <20110325044754.GK26611@dastard> <20110325222458.GB26932@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton , Christoph Hellwig , Wu Fengguang To: Jan Kara Return-path: Content-Disposition: inline In-Reply-To: <20110325222458.GB26932-+0h/O2h83AeN3ZZ/Hiejyg@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Mar 25, 2011 at 11:24:58PM +0100, Jan Kara wrote: > So I think we could stop doing writeback when we have done the transition > of pages from Dirty to Writeback state. We should only make sure someone > kicks the background writeback again when there are enough unstable pages > to be worth a commit. This tends to happen from balance_dirty_pages() or > in the worst case when flusher thread awakes to check for old inodes to > flush. But we can also kick the flusher thread from NFS when we transition > enough pages which would seem rather robust to me. I'll try to write a > patch in this direction. I think making the background writeback commits triggered by NFS write completion is a good way to proceed. A write request completion gives us a guaranteed context to determine if we need to issue a commit or not and should mostly avoid the need for polling or some external event to trigger a threshold check. Cheers, Dave. -- Dave Chinner david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html