homerun wrote:
been using now zfs since 06/06 u2 release has been out. one thing have notised. zfs eats a lot of memory. right after boot mem usage is about 280M but after accessing zfs disks usage rises fast to be 900M. and it seems to stay in level of 90% of tot mem. also noted it frees used mem but running "heavy" apps you see performace impact while zfs frees memory to other use.
Yes, that is the case. As I understand things it's an artefact of how zfs is implemented. There are changes in the Solaris 10 patch pipeline which should make the kmem usage somewhat better.
now idea: could there be /etc/system tunable parameter for zfs so we could manually set % of total memory zfs can use. like : zfs_max_phys_mem 30% would tell zfs that it can use 30% of available memory. and via versa zfs_min_phys_mem 10% would tell zfs that it can allways use 10% of available memory. --> these maybe need to global values for all zfs filesystems or just simple zfs option that can be set as other zfs options , like compression, etc... then this setting could be easily per zfs filesystem
I understand the concern, but I'm not sure that this is the best way of achieving your goal. What would you want to observe if your system hit the upper limit in zfs_max_phys_mem? cheers, James C. McPherson _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
