> I have just (re)installed FreeBSD amd64 current with gcc 4.2 with src
> from May. 21'st on a dual Dell PE 2850. Does the post-gcc-4-2 current
> include all your zfs-optimizations?
>
> I have commented out INVARIANTS, INVARIANTS_SUPPORT, WITNESS and
> WITNESS_SKIPSPIN in my kernel and recompiled with CPUTYPE=nocona.
>
> A default install solaris fares better io-wise compared to a default
> FreeBSD where writes could pass 100 MB/s (zpool iostat 1) and FreeBSD
> would write 30-40 MB/s. After adding the following to
> /boot/loader.conf writes peak at 90-95 MB/s:
>
> vm.kmem_size_max=2147483648
> vfs.zfs.arc_max=1610612736
>
> Now FreeBSD seems to perfom almost as good as solaris io-wise although
> I don't have any numbers to justify my statement. I did not import
> postgresql in solaris as one thing.
>
This patch also improve concurrency in VFS:
http://people.freebsd.org/~pjd/patches/vfs_shared.patch
I applied the patch and it seems to speed up my reads and writes.
Watching zpool iostat I saw reads at 155 MB/s and writes at 111 MB/s.
But it also seems to introduce some minor complete stops accessing the
zpool lasting for 10-20 secs. I apologize I'm not very specific but I
only had time to test disk-io but not digg into the issues.
When you want to operate on mmap(2)ed files, you should disable ZIL and
remote file systems:
# sysctl vfs.zfs.zil_disable=1
# zpool export <name>
# zpool import <name>
Won't disabling ZIL minimize the chance of a consistent zfs-filesystem
if - for some reason - the server did an unplanned reboot?
--
regards
Claus
When lenity and cruelty play for a kingdom,
the gentlest gamester is the soonest winner.
Shakespeare
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
