On Friday 22 January 2010, Nigel Cunningham wrote: > Hi. > > Rafael J. Wysocki wrote: > > On Friday 22 January 2010, Leisner, Martin wrote: > >> I noticed when we enter sleep states, it seems there's always a > >> sys_sync given. > >> > >> When having an embedded system doing WOL (already in laptop mode to > >> cache > >> all the writes), it reasonable to wake up dozens of times of day and > >> quickly go back to sleep. If the disk is not spun up, > >> and there's some work to be done, won't the sys_sync spin up the disk > >> before going to sleep? > >> > >> It would be good to have a knob (in /sys) you can tweak from usespace to > >> > >> configure the behavior of whether you want to do a sync when entering > >> sleep. > >> > >> The ideal behavior would be: > >> > >> if(disk is spun up) > >> then let the sync happen > > > > I'm not against that. Patch welcome. :-) > > Oooh. I am. That's providing potential for unpredictable behaviour. Much > better IMO would be providing a tuning know that explicitly and > unconditionally disables syncing. You're right, sorry. Yes, a knob that disables syncing unconditionally was the thing I was thinking about. Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
