thoughts from two guys

So I'm attempting to prep a build box for Centos 5.5 and ZFS+ZPL testing.

First off we are going to run the "kernel-ml" or mainline kernel on the system which is part of the fine EPEL repository.

rpm -Uvh http://elrepo.org/elrepo-release-5-2.el5.elrepo.noarch.rpm
yum --enablerepo=elrepo-kernel install kernel-ml kernel-ml-devel

Reboot and we're in 2.6.37 land. HOLD UP: THAT MAY BE TOO NEW.

Linux localhost.localdomain 2.6.37-0.3.el5.elrepo #1 SMP PREEMPT Mon Feb 7 17:31:48 EST 2011 x86_64 x86_64 x86_64 GNU/Linux

Then we are downloading and installing the development versions from the ZFS site.

Then we build them.

mkdir zfs
cd zfs
(download from zfs developer version)
tar zxvf behlendorf-spl-spl-0.5.2-23-g22ccfaa.tar.gz
cd behlendorf-spl-22ccfaa/
./configure 
make install
modprobe spl

So far so good:

SPL: Loaded Solaris Porting Layer v0.6.0

On to the ZFS module itself.

tar zxvf behlendorf-zfs-zfs-0.5.2-69-g2c395de.tar.gz 
cd behlendorf-zfs-2c395de/
./configure

We hit a few issues with missing defines for the zfs build so we hack around it with these defines.

Added to deal with undefined items on line 310 of libzfs_mount.c:

#define MNT_FORCE       0x00000001      /* Attempt to forcibily umount */
#define MNT_DETACH      0x00000002      /* Just detach from the tree */
#define MNT_EXPIRE      0x00000004      /* Mark for expiry */

Later in modules/zfs we seem to hit a missing kernel API routine invalidate_inodes. We work around it and vow to do further research

modprobe zfs
ZFS: Loaded ZFS Filesystem v0.6.0

OK, now attaching a disk.

zpool create data01 sdb1
# zpool list
NAME     SIZE  ALLOC   FREE    CAP  DEDUP  HEALTH  ALTROOT
data01    37G    81K  37.0G     0%  1.00x  ONLINE  -
# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/sda1             37690316   2006484  33738364   6% /
tmpfs                   511360         0    511360   0% /dev/shm
data01                38190976         0  38190976   0% /data01
# zpool upgrade -v
This system is currently running ZFS pool version 28.

The following versions are supported:

VER  DESCRIPTION
---  --------------------------------------------------------
 1   Initial ZFS version
 2   Ditto blocks (replicated metadata)
 3   Hot spares and double parity RAID-Z
 4   zpool history
 5   Compression using the gzip algorithm
 6   bootfs pool property
 7   Separate intent log devices
 8   Delegated administration
 9   refquota and refreservation properties
 10  Cache devices
 11  Improved scrub performance
 12  Snapshot properties
 13  snapused property
 14  passthrough-x aclinherit
 15  user/group space accounting
 16  stmf property support
 17  Triple-parity RAID-Z
 18  Snapshot user holds
 19  Log device removal
 20  Compression using zle (zero-length encoding)
 21  Deduplication
 22  Received properties
 23  Slim ZIL
 24  System attributes
 25  Improved scrub stats
 26  Improved snapshot deletion performance
 27  Improved snapshot creation performance
 28  Multiple vdev replacements
#

Time to break some data!

So in case you've not heard, Oracle made some changes to the way OpenSolaris was being released that basically for practical sakes killed that branch of open source Solaris and with it our primary way of doing production level ZFS. For lower cost anyway.

So we've been tracking these developments very closely in looking for a solid ZFS solution for what we use it for: dedupe and backups of our cluster filesystems.

FreeBSD version v28 ZFS has been added to 8-STABLE as a patch and so far seems pretty solid. Some outstanding work for those that want a quick install (and even root filesystems on ZFS) is located here .

For those that like to build their own, the patch area listed there should be tracked against the SVN checkout of FreeBSD or it doesn't quite apply properly.

But the cool part is after those patches you do indeed get a v28 capable ZFS in 8-STABLE.

bsd81# zpool upgrade -v
This system is currently running ZFS pool version 28.

The following versions are supported:

VER  DESCRIPTION
---  --------------------------------------------------------
 1   Initial ZFS version
 2   Ditto blocks (replicated metadata)
 3   Hot spares and double parity RAID-Z
 4   zpool history
 5   Compression using the gzip algorithm
 6   bootfs pool property
 7   Separate intent log devices
 8   Delegated administration
 9   refquota and refreservation properties
 10  Cache devices
 11  Improved scrub performance
 12  Snapshot properties
 13  snapused property
 14  passthrough-x aclinherit
 15  user/group space accounting
 16  stmf property support
 17  Triple-parity RAID-Z
 18  Snapshot user holds
 19  Log device removal
 20  Compression using zle (zero-length encoding)
 21  Deduplication
 22  Received properties
 23  Slim ZIL
 24  System attributes
 25  Improved scrub stats
 26  Improved snapshot deletion performance
 27  Improved snapshot creation performance
 28  Multiple vdev replacements

We are doing heavy testing to make sure its reliable and watching for a formal commit.

On the Linux ZFS front we continue to watch closely the efforts of the native kernel module. While we have no issue with the FUSE approach, we like to have as many options as we can. We have used the FUSE modules for ZFS successfully.

That work continues at the primary release site and the ZPL portion was recently added to a development branch. We are testing that as well under Centos based kernels.

Finally, we watch two OpenSolaris based spin-offs just to cover all the bases:

OpenIndiana

And Nexenta's release of the core OS.

Nexenta CP

Despite the fact it appears we are very quiet here its due to being busy. But I thought I'd write up a few battles of late in the hopes some find them interesting! Stay tuned!