Hi Christoph! On Tue 19-07-22 06:13:07, Christoph Hellwig wrote: > this series removes iomap_writepage and it's callers, following what xfs > has been doing for a long time. So this effectively means "no writeback from page reclaim for these filesystems" AFAICT (page migration of dirty pages seems to be handled by iomap_migrate_page()) which is going to make life somewhat harder for memory reclaim when memory pressure is high enough that dirty pages are reaching end of the LRU list. I don't expect this to be a problem on big machines but it could have some undesirable effects for small ones (embedded, small VMs). I agree per-page writeback has been a bad idea for efficiency reasons for at least last 10-15 years and most filesystems stopped dealing with more complex situations (like block allocation) from ->writepage() already quite a few years ago without any bug reports AFAIK. So it all seems like a sensible idea from FS POV but are MM people on board or at least aware of this movement in the fs land? Added a few CC's for that. Honza > Changes since v1: > - clean up a printk in gfs2 > > Diffstat: > fs/gfs2/aops.c | 26 -------------------------- > fs/gfs2/log.c | 5 ++--- > fs/iomap/buffered-io.c | 15 --------------- > fs/zonefs/super.c | 8 -------- > include/linux/iomap.h | 3 --- > 5 files changed, 2 insertions(+), 55 deletions(-) -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
