On 06/20/2017 02:57 AM, Christoph Hellwig wrote: > On Mon, Jun 19, 2017 at 02:33:41PM -0600, Jens Axboe wrote: >> That doesn't work, in case it's cleared, or for checking whether it has >> been set or not. Oh well, I added a NOT_SET variant for this. See below >> for an incremental that adds support for file write hints as well. Use >> the file write hint, if we have it, otherwise use the inode provided >> one. >> >> Setting hints on a file propagates to the inode, only if the inode doesn't >> currently have a hint set. > > Question: IFF we can get the per-file hints to propagate to the > writeback code (which I think is pretty easy for ext4/xfs/bdev, not > sure about btrfs) do we even need the per-inode ones at all? How is that possible, the file could be long gone by the time the writeback kicks in? -- Jens Axboe