On Wed, Nov 28, 2007 at 11:29:57AM -0800, Michael Rubin wrote: > >From [EMAIL PROTECTED] Wed Nov 28 11:10:06 2007 > Message-Id: <[EMAIL PROTECTED]> > Date: Wed, 28 Nov 2007 11:01:21 -0800 > From: [EMAIL PROTECTED] > To: [EMAIL PROTECTED] > Subject: [patch 1/1] Writeback fix for concurrent large and small file writes. > > From: Michael Rubin <[EMAIL PROTECTED]> > > Fixing a bug where writing to large files while concurrently writing to > smaller ones creates a situation where writeback cannot keep up with the
Could you demonstrate the situation? Or if I guess it right, could it be fixed by the following patch? (not a nack: If so, your patch could also be considered as a general purpose improvement, instead of a bug fix.) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 0fca820..62e62e2 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -301,7 +301,7 @@ __sync_single_inode(struct inode *inode, struct writeback_control *wbc) * Someone redirtied the inode while were writing back * the pages. */ - redirty_tail(inode); + requeue_io(inode); } else if (atomic_read(&inode->i_count)) { /* * The inode is clean, inuse Thank you, Fengguang > traffic and memory baloons until the we hit the threshold watermark. This > can result in surprising latency spikes when syncing. This latency > can take minutes on large memory systems. Upon request I can provide > a test to reproduce this situation. The flush tree fixes this issue and > fixes several other minor issues with fairness also. > > 1) Adding a data structure to guarantee fairness when writing inodes > to disk. The flush_tree is based on an rbtree. The only difference is > how duplicate keys are chained off the same rb_node. > > 2) Added a FS flag to mark file systems that are not disk backed so we > don't have to flush them. Not sure I marked all of them. But just marking > these improves writeback performance. > > 3) Added an inode flag to allow inodes to be marked so that they are > never written back to disk. See get_pipe_inode. > > Under autotest this patch has passed: fsx, bonnie, and iozone. I am > currently writing more writeback focused tests (which so far have been > passed) to add into autotest. > > Signed-off-by: Michael Rubin <[EMAIL PROTECTED]> > --- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/