After checking 2.6.35 kernel source code, POSIX_FADV_NOREUSE actually doesn't do anything. So I don't know how it helps. Probably we should do POSIX_FADV_DONTNEED after reading?
Jay On Mar 17, 2011, at 5:43 PM, Oleg Drokin wrote: > Hello! > > On Mar 17, 2011, at 5:44 PM, Andreas Dilger wrote: >>> I did not find if this was removed or this was partially included in >>> Lustre 2.0. >>> What's the current status of this and how can I tell to my client to >>> avoid caching too many data? >> The client VM usage was one of the areas that was completely rewritten by >> Nikita for 2.0, so it was likely this functionality was lost at that time. >> I don't have any idea at this time how hard it would be to restore. > > I wonder if the generic vm tunables could be used instead? I think that was > the original plan. > >>> Those clients do a lot of read and write in Lustre filesystems but >>> thoses files will not be re-read soon, so it is useless to fill memory >>> with it. Moreover, when the client memory is full, Lustre performance >>> are really impacted. >> It may be possible to use fadvise(FADV_NOREUSE) from the application to >> cause the VM to discard these pages after the first use. > > Yes, that would totally make sense to do regardless of other methods. > > Bye, > Oleg > _______________________________________________ > Lustre-discuss mailing list > [email protected] > http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
