On 2010-02-15 02:25:57PM -0800, Artem Belevich wrote: > > How much ram are you running with? > > 8GB on amd64. kmem_size=16G, zfs.arc_max=6G > > > In a latest test with 8.0-R on i386 with 2GB of ram, an install to a ZFS > > root *will* panic the kernel with kmem_size too small with default > > settings. Even dropping down to Cy Schubert's uber-small config will panic > > the kernel (vm.kmem_size_max = 330M, vfs.zfs.arc_size = 40M, > > vfs.zfs.vdev.cache_size = 5M); the system is currently stable using DIST > > kernel, vm.kmem_size/max = 512M, arc_size = 40M and vdev.cache_size = 5M. > > On i386 you don't really have much wiggle room. Your address space is > 32-bit and, to make things more interesting, it's split between > user-land and kernel. You can keep bumping KVA_PAGES only so far and > that's what limits your vm.kmem_size_max which is the upper limit for > vm.kmem_size. > > The bottom line -- if you're planning to use ZFS, do switch to amd64. > Even with only 2GB of physical RAM available, your box will behave > better. At the very least it will be possible to avoid the panics > caused by kmem exhaustion. > > --Artem
Well this ZFS box (which admittedly is mostly a testbed) is only a lowly NetBurst Gallatin Xeon, pre-amd64 :( -- =========================================================== Peter C. Lai | Bard College at Simon's Rock Systems Administrator | 84 Alford Rd. Information Technology Svcs. | Gt. Barrington, MA 01230 USA peter AT simons-rock.edu | (413) 528-7428 =========================================================== _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"