Using an SSD for FreeNAS installation AND intent log?

[Cainram]

It has been years since I've used FreeNAS and I'm really excited to try ZFS! I'm installing FreeNAS 9.2.1.5 on an early 2008 Mac Pro with 20gb of RAM. I have a 120gb SSD and I didn't want to 'waste' it on the OS but I'm having a heck of a time booting from USB so... Here's what I propose: A small partition for the OS and a larger partition for the ZFS intent log. Does this make sense? Is it possible? If so, how should I go about making this happen?
I'm no *nix noob and I've been using Linux/BSD/etc. for many years. I'm just getting old and lazy and this is a specialty thing so I figured you wonderful people in the FreeNAS community would be happy to steer me in the right direction.

I'm having problems booting the installation with the old 'mountroot' issue but I'll figure that out on my own. The question here is academic: can this be done and, if so, what is the best course of action?

Thanks in advance!

Edit: I solved the mountroot issue and put my results in a recent post: http://forums.freenas.org/index.php?threads/going-crazy-with-mount-root-from-error.894/

 

[cyberjock]

If you read the manual it says that the OS media cannot be used for anything else, and that is exactly correct. MBR can only have 4 partitions and FreeNAS requires 4 partitiosn. So yeah, no options.

Even *if* you could use a partition for ZFS intent log, it wouldn't go well and I wouldn't recommend it anyway.

 

[Cainram]

OK, thanks for the reply. I knew that you can't use the boot drive for data storage but I forgot that the reason for that is the partition limitation.

Here's what I think I'll do: I'll install OS X to the SSD and use rEFIt to boot to a USB stick with FreeNAS installed. I'll then partition off most of the SSD for the intent log.

Here is my question now - will I get a noticeable boost in performance by doing so? The NAS will be idle probably 90% of the time. I'm going to use it to serve movies and music to my Mac computers and Android devices. I want to run Bittorrent Sync to keep my work computer backed up (Ubuntu 14.04) and I will probably never have more than three clients connected at any given time. I'll have 2 2b drives mirrored and a handful of other drives connected via USB (not in a RAID). I have 20gb RAM.

Thoughts?

 

[anodos]

A separate intent log is only useful if you have lots of sync writes. It should be kept small (probably no more than a couple of gigabytes). It also introduces a single point of failure to your zpool, as well as complexity to your setup.

Read the information here: http://forums.freenas.org/index.php...ning-vdev-zpool-zil-and-l2arc-for-noobs.7775/

Overall, I think you should probably configure without a slog. Add one if and only if you have verified that you are performing lots of synchronous writes to your zpool and will benefit from adding it..

 

[Cainram]

That is great news and pretty much what I wanted to hear. Now I can swap the SSD for a small HDD for booting and use the SSD in a desktop. Thanks!