On Wed, Sep 26, 2012 at 06:59:00AM +0530, Raghavendra D Prabhu wrote: > Hi, > > > * On Sat, Sep 22, 2012 at 08:49:20PM +0800, Fengguang Wu <fengguang.wu@xxxxxxxxx> wrote: > >On Sat, Sep 22, 2012 at 04:03:11PM +0530, raghu.prabhu13@xxxxxxxxx wrote: > >>From: Raghavendra D Prabhu <rprabhu@xxxxxxxxxxx> > >> > >>If page lookup from radix_tree_lookup is successful and its index page_idx == > >>nr_to_read - lookahead_size, then SetPageReadahead never gets called, so this > >>fixes that. > > > >NAK. Sorry. It's actually an intentional behavior, so that for the > >common cases of many cached files that are accessed frequently, no > >PG_readahead will be set at all to pointlessly trap into the readahead > >routines once and again. > > ACK, thanks for explaining that. However, regarding this, I would > like to know if the implications of the patch > 51daa88ebd8e0d437289f589af29d4b39379ea76 will still apply if > PG_readahead is not set. Would you elaborate the implication and the possible problematic case? 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>