On Friday 02 September 2005 14:10, Con Kolivas wrote: > Yes that about wraps up what it does. It would be even better used in a > real world situation on a machine that has trouble "getting started" after > an overnight updatedb run and has been idle for a while.
thanks. your last comment about updatedb reminds me of my "server"'s kind of load :-p > > about the Hans's proposal - it would increase power consumption, because > > of increased disk activity. about con's swap prefetch, I'm not so sure... > > Depends entirely on workload. Overall I think this increases power > consumption because the disk does tiny little reads and keeps spinning > until it has finished prefetching as much as it can. I was thinking it > could be made configurable and to detect when laptop mode was enabled and > so on... if it is thought that this is desirable of course. Not counting hard drive spin-down or even standby, I find no reason for increased power consumption on swap prefetch mechanism, except for page syncing (swap&mem) and perhaps upon process killing... Question: Imagine some big app like firefox completely swapped. killing it implies swapping out the process memory entirely to free allocated pages? - If it does, then your swap prefetch may not increase power consumption by a measurable margin, because some of that swapped information was prefetched. - If it does not, than prefetched swapped pages could be useless if the applications dies. I don't know enough about the kernel VM to answer this on my own. regards, pedro venda. -- Pedro João Lopes Venda email: pjvenda < at > arrakis.dhis.org http://arrakis.dhis.org
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