On 10/26/2012 11:25 AM, Miao Xie wrote: > On Fri, 26 Oct 2012 10:05:55 +0800, Liu Bo wrote: >> On 10/26/2012 09:56 AM, Miao Xie wrote: >>>> I can see the potential improvements brought by flushing inodes this way. >>>>> >>>>> But I don't think it makes much sense by making waiting process multi-task, >>>>> since even we spread wait order extents into different cpus, they just occpied >>>>> the cpu and went on waiting and scheduled then, I mean, the bottleneck is on >>>>> what we're waiting for. >>> Thanks for your comment, I think only btrfs_run_ordered_operations(root, 0) needn't >>> wait for the works, the others must wait. >>> >>> The first reason is to avoid changing the semantic of those tree function. The second >>> reason is we have to wait for the completion of all works, if not, the file data in >>> snapshots may be different with the source suvolumes because the flush may not end >>> before the snapshot creation. >>> >> >> Yes, it's right that they must wait for all workers to finish. >> >> But I don't mean that(sorry for my confusing words). >> >> IMO we don't need to let *btrfs_wait_ordered_extents()* run as multi-task. > > It also need to be done by multi-task because btrfs_wait_ordered_extents() doesn't imply > that all the dirty pages in the ordered extent have been written into the disk, that is > it also need do lots of things before waiting for the event - BTRFS_ORDERED_COMPLETE, so > the multi-task process is useful, I think. > Well, I missed the flushing part. > Anyway, we need test to validate it. > > Thanks > Miao > >> >> thanks, >> liubo >> >> >> >> > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
