See comments inline below:
> > You can limit the amount of memory that ZFS uses > for its cache (the ARC - Adaptive Replacement Cache) > as described here: > > > > > http://www.solarisinternals.com/wiki/index.php/ZFS_Evi > l_Tuning_Guide#Limiting_the_ARC_Cache > > > > In fact the live CD does just that in order to > allow OpenSolaris to install on systems with only > 512MB memory - check /etc/system while booted from > the live CD to see what it is set to. > > > > Cheers > > > > Andrew. > > > Hi, I do NOT wish to hijack this thread but have a > question related to this > answer: > > what is the advantage or disadvantage of limited the > ZFS cache??? Read the page I linked to. > > Additionally does it depend on system size; ie. how > large the - and how > many hard disks there are?? The *maximum* ARC size is based on the total amount of RAM in the system if I recall correctly. It will default to 7/8ths of available RAM, or RAM minus 1G - whichever is greater. It starts of small but gets bigger as more stuff is read off disk. The ARC is shared between all ZFS pools and filesystems which you have active on the system - again see the page I linked to for more details. > > So say for a system with 2GB memory if the app + > kernel + background > procs takes up 1.5GB then if one limits the ZFS cache > to 512MB what > significance does this have?? It means your background processes get less of a hard time from the ARC cache as they fight for memory, since the ARC will not attempt to grow beyond 512MB. You will probably want to have a play with it and see what the effect is on your actual system - it may take a bit of trial and error to get the right setting for your particular circumstances. > > Regards and apologies for the intrusion!! Not a problem ;-) Andrew. > > Kaya > _______________________________________________ > opensolaris-help mailing list > opensolaris-help@opensolaris.org -- This message posted from opensolaris.org _______________________________________________ opensolaris-help mailing list opensolaris-help@opensolaris.org
