On Fri, Aug 20, 2010 at 05:31:29PM +0800, Michael Rubin wrote: > The kernel already exposes the user desired thresholds in /proc/sys/vm > with dirty_background_ratio and background_ratio. But the kernel may > alter the number requested without giving the user any indication that > is the case. > > Knowing the actual ratios the kernel is honoring can help app developers > understand how their buffered IO will be sent to the disk. > > $ grep threshold /proc/vmstat > nr_dirty_threshold 409111 > nr_dirty_background_threshold 818223 I realized that the dirty thresholds has already been exported here: $ grep Thresh /debug/bdi/8:0/stats BdiDirtyThresh: 381000 kB DirtyThresh: 1719076 kB BackgroundThresh: 859536 kB So why not use that interface directly? Thanks, Fengguang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>