* Wu Fengguang <fengguang.wu@xxxxxxxxx> wrote: > On Wed, Nov 30, 2011 at 01:57:43AM +0800, Andi Kleen wrote: > > On Tue, Nov 29, 2011 at 09:09:03PM +0800, Wu Fengguang wrote: > > > Record the readahead pattern in ra->pattern and extend the ra_submit() > > > parameters, to be used by the next readahead tracing/stats patches. > > > > I like this, could it be exported it a bit more formally in /proc for > > each file descriptor? > > How about this? > --- > Subject: proc: show readahead state in fdinfo > Date: Thu Dec 15 14:35:56 CST 2011 > > Append three readahead states to /proc/<PID>/fdinfo/<FD>: Not a very good idea - please keep debug info under /debug as much as possible (as your original series did), instead of creating an ad-hoc insta-ABI in /proc. In the long run we'd really like to retrieve such kind of information not even via ad-hoc exported info in /debug but via the standard event facilities: the tracepoints, if they are versatile enough, could be used to collect these stats and more. Thanks, Ingo -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>