Re: regression in page writeback

Christoph Hellwig
2009-09-28T13:08:13Z

On Mon, Sep 28, 2009 at 03:15:07PM +0800, Wu Fengguang wrote:
> + if (!PageActive(page))
> + SetPageReclaim(page);
> + err = mapping->a_ops->writepage(page, wbc);
> + if (err < 0)
> + handle_write_error(mapping, page, res);
> + if (err == AOP_WRITEPAGE_ACTIVATE) {
> + ClearPageReclaim(page);
> + res = PAGE_ACTIVATE;
> + break;
> + }

This should help a bit for XFS as it historically does multi-page
writeouts from ->writepages (and apprently btrfs that added some
write-around recently?) but not those brave filesystems only
implementing the multi-page writeout from writepages as designed.

But really, the best would be to leave the writeout to the flusher
threads and just reclaim the clean pages from the VM.