On Thu, Jun 09, 2011 at 05:09:06PM +0800, Wu Fengguang wrote: > I have a sync livelock test script and it sometimes livelocked on XFS > even with the livelock fix patches. Ext4 is always OK. This sounds similar to the cfq issue just posted to lkml as "CFQ: async queue blocks the whole system". Does this happen with non-CFQ I/O schedulers, too? > [ 3581.185120] [<ffffffff812ed520>] xfs_ioend_wait+0x87/0x9f This waits for the I/O completion to actually arrive - something that XFS does correctly in both sync and fsync, but ext4 only does for fsync. It might have some issues in the way it's implemented, I'll look if we can do something. But I suspect cfq delaying async writes too much is definitively going to cause issues for us here. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
