* KOSAKI Motohiro <kosaki.motoh...@jp.fujitsu.com> [2011-04-01 16:56:57]:
> Hi
>
> > > 1) zone reclaim doesn't work if the system has multiple node and the
> > > workload is file cache oriented (eg file server, web server, mail
> > > server, et al).
> > > because zone recliam make some much free pages than zone->pages_min and
> > > then new page cache request consume nearest node memory and then it
> > > bring next zone reclaim. Then, memory utilization is reduced and
> > > unnecessary LRU discard is increased dramatically.
> > >
> > > SGI folks added CPUSET specific solution in past.
> > > (cpuset.memory_spread_page)
> > > But global recliam still have its issue. zone recliam is HPC workload
> > > specific
> > > feature and HPC folks has no motivation to don't use CPUSET.
> >
> > I am afraid you misread the patches and the intent. The intent to
> > explictly enable control of unmapped pages and has nothing
> > specifically to do with multiple nodes at this point. The control is
> > system wide and carefully enabled by the administrator.
>
> Hm. OK, I may misread.
> Can you please explain the reason why de-duplication feature need to
> selectable and
> disabled by defaut. "explicity enable" mean this feature want to spot corner
> case issue??
>
Yes, because given a selection of choices (including what you
mentioned in the review), it would be nice to have
this selectable.
--
Three Cheers,
Balbir
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
