A Closer Look at ZFS, Vdevs and Performance

Constantin gives here an great introduction into ZFS, vdevs and performance.

FreeNAS vs Nexentastor

I've tested the performance of FreeNAS 0.7.1 stable (Build 5127) and Nexentastor Community Edition 3.0.2. I will not dig into the different features or the details of both WebGUIs.

For the tests I've used the following hardware

Server

CPU - Intel Core2Duo E6300 - 1.8 GHz - 2 MB Cache

RAM - 2 GByte

Mainboard - Intel DG965WH

Harddisks - 3x WesternDigital WD3200 (320 GByte connected to the onboard SATA2)

Client

My good old MacBook Pro (late 2008), 4 GByte RAM, Mac OS X 10.6.3

Software
iSCSI initiator - Global SAN iSCSI initiator (4.0.0.204)
Benchmark Software - XBench

Benchmark Software - Helios LAN Test

Benchmark Software - iozone (MacPorts)

Protocols

CIFS
NFS
AFP (currently only available for FreeNAS)
iSCSI

Benchmarks
Xbench - The best out of 5 results
Helios LAN Test - 10 tests, two times, best result
iozone - options -e -i0 -i1 -i2 -+n -r 256k -s2g -t4 -c -x

Tuning

No tuning on the Nexentastor. For FreeNAS I've enabled in the WebGUI System | Advanced | Tuning (enable tuning of some kernel variables)

CIFS
Keep in mind, I've tested CIFS with the built-in smb client of OSX. A native Windows OS might provide different results.

Tuning for FreeNAS (via WebGUI)

Services | CIFS/SMB | Settings

-> Send and Receive Buffer Size to 65535

-> Enable large read/write

-> Auxiliary parameters : max xmit = 65535

-> Auxiliary parameters : socket options = TCP_NODELAY SO_SNDBUF=65535 SO_RCVBUF=65535

If you compare the CIFS results you will see that NexentaStor is slightly faster than FreeNAS

NFS
I wasn't able to get XBench to run on a FreeNAS NFS mountpoint. So you wont see any results on the XBench charts.




With the missing XBench results for FreeNAS I would say NexentaStor is here the winner. It provides slightly higher throughput rates.

AFP
NexentaStor doesn't provide this protocol. As I am a Mac user it is very useful to have a system serving data via AFP. Especially the support of FreeNAS for time machine is IMHO excellent (see my blogposts about backup and restore using FreeNAS and time machine)




FreeNAS is in this disciplin the clear winner.

iSCSI
There was also an issue to get iozone to run on a FreeNAS iSCSI target.





The iSCSI protocol shows several advantages compared to the other. It shows high throughput rates with a low latency. But it is not usable to share the LUN to several systems at the same time (it is possible with special Filesystems, I know, but I think this is not very common). With the lack of the iozone results for FreeNAS I would also say, Nexentastor is here the winner.

Overall comparisson











Conclusion
FreeNAS and Nexenta is on the performance side very much comparable. NexentaStor is slitghly faster in most of the disciplines, but the lack of AFP make them both overall equal.
FreeNAS is easy to setup and has a very clear and structured WebGUI. Nexenta has more features (e.g. built in snapshots, deduplication, etc.)

At the moment I definitely will stay with FreeNAS as the performance is comparable and I really like the integration of Time Machine via AFP.

P.S.: If you are interested in a detailed Excel-Sheet with more details, please drop me a mail harryd71 at users dot sourceforge dot net

Flattr

I've stumbled upon flattr :-)

Flattr is a social micropayment platform that lets you show love for the things you like.

As I've always looked for a service like this to show other people my respect and want to give them something back, I think this might be the right platform to do this. I've added a button to each of my blogposts and if you like what you read, you can press this button.

Of course, you need to be a user of this service, so please register for a beta invite or ask me at harryd71 at users dot sourceforge dot net or send me a direct message on twitter.

Many thanks for your support!

P.S.: Nico showed on this blogpost how to add a flattr button to blogger. Many thanks, Nico (of course, I've flattr'd you :-) )

Where is harryd?

Maybe you've recognized that I am not very active here or at the FreeNAS forum.

The reason behind this... I build together with my wife, our own house. She is the architect and there is a lot of work to do. To be honest... If you see our piece of land, you won't see too much, as the craftsmen just begun. But there is a lot of work to do behind the scenes.

The next few weeks / months will be very exciting, as we can see how our dream is built in stone and wood (and all the other materials). There is a lot of work to do for me, as I will do the whole electricity (and a few other things).

I've prepared another blogpost and I hope I'm able to finish it soon. So, please stay tuned and thanks for all your feedback!

Mac OS X system restore using time machine and FreeNAS

I'd like to show you in this post how you can recover your Mac from a time machine backup using FreeNAS. If you've set up time machine as I've described here, you should be able to do a complete system restore.

I've used a virtual machine using VirtualBox 3.2.0 on my MacMini to demonstrate this. VirtualBox supports now to install Mac OS X guests (maybe not for a very long time, AFAIK this is not allowed by Apple.)

1. If you have an issue with your system and you want to do a complete restore (or disaster recovery), please boot from the original boot DVD

2. Choose 'Restore System From Backup...' the 'Utilities' menu

3. Click 'Continue'. The next screen will show you the available sources.

4. After entering your login credentials you should see the backup source for your system

5. The next screen shows you the available backups of your system. Select the one you've want to restore

6. Select the destination disk and click 'restore' read the warning and 'continue'

7. And finally restart the system

Lots of information about ZFS and storage

Seeding FreeNAS 0.7.1 stable (5127)

You will find the .torrent files here -> TBP...

Please help to seed

Seeding FreeNAS 0.7 stable (4919)

You will find the .torrent files here -> TBP...

Please help to seed!