On Tue, Oct 16, 2012 at 11:45:21PM +0530, Raghavendra D Prabhu wrote: > Hi, > > > * On Sat, Sep 22, 2012 at 08:42:50PM +0800, Fengguang Wu <fengguang.wu@xxxxxxxxx> wrote: > >it.rprabhu@xxxxxxxxxxx> > >User-Agent: Mutt/1.5.21 (2010-09-15) > >X-Date: Sat Sep 22 18:12:50 IST 2012 > > > >On Sat, Sep 22, 2012 at 04:03:13PM +0530, raghu.prabhu13@xxxxxxxxx wrote: > >>From: Raghavendra D Prabhu <rprabhu@xxxxxxxxxxx> > >> > >>page_cache_sync_readahead checks for ra->ra_pages again, so moving the check > >>after VM_SequentialReadHint. > > > >Well it depends on what case you are optimizing for. I suspect there > >are much more tmpfs users than VM_SequentialReadHint users. So this > >change is actually not desirable wrt the more widely used cases. > > shm/tmpfs doesn't use this function for fault. They have shmem_fault > for that. So, that shouldn't matter here. Agree? That's true for the regular tmpfs and it still calls filemap_fault() in the !CONFIG_SHMEM case and squashfs/cramfs etc. They together should still overweight the VM_SequentialReadHint users? Thanks, Fengguang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>