RAID 5 (4x 500gb) w/ 100gb partition for system?

This is how my 2 x 2.66 GHz Dual-Core Xeon Mac Pro is set up right now. I spend most days in many of the CS3 Production Premium programs and I am not getting the performance that I think I should be getting.
Does this RAID setup sound like trouble? My IT dept. needs to have the system on a separate partition or HD, and at the time I set this up I didn't have an external backup option. Now I have access to a server for backups.
I'm thinking now that I should have 1 of my 4 drives as the system drive and RAID 0 the other three. IT doesn't want to spend all day on my computer unless this is going to make a difference though so I'm asking around for advice from other users.

What do you guys think.

handling drives

Corbin Gross said:

This is how my 2 x 2.66 GHz Dual-Core Xeon Mac Pro is set up right now. I spend most days in many of the CS3 Production Premium programs and I am not getting the performance that I think I should be getting.
Does this RAID setup sound like trouble? My IT dept. needs to have the system on a separate partition or HD, and at the time I set this up I didn't have an external backup option. Now I have access to a server for backups.
I'm thinking now that I should have 1 of my 4 drives as the system drive and RAID 0 the other three. IT doesn't want to spend all day on my computer unless this is going to make a difference though so I'm asking around for advice from other users.

What do you guys think.

Click to expand...

I think you have a situation that requires a little thought here.

There are several scenarios and being from the IT world myself, I understand why they think
having your OS in a separate partition or drive is useful. You didnt mention what type of back
ups are going to the network server.

If they are doing a real back up that can be totally restored (an image) of your system then there
is no need to isolate the Operating System. In fact, if their notion is to "over install" an OS if your
system gets corrupted is their motive - then you would need to re-install your apps as well as
references would be lost (plists, settings etc). Alternatively they may install the OS then restore
the other locations from your drive(s) and overlay the references/configurations. This is important
and reflects on how you want to set up your system.

A conservative approach for speed -
1) remove one drive and replace with a 1.5 tb drive.
2) raid 3 drives and put everything on them.
3) use the internal 1.5 tb drive as a clone of your raid system (backup local)
4) boot to the 1.5 tb at appropriate times (I'll explain in a moment)
5) Make sure to configure your CS3 apps. I.e. scratch file size, history settings etc.
6) Keeping your drive(s) frag free.

Of the latter, when working with media files its very easy to frag your drive. There are a few
things you can do to keep your system running fast.

1) Raid set up - there is an advance option for block size ranging from 32k to 256k.
If you really work with large files, you will want 128 or 256k. If you work with a lot
of large and small files, then 128k is a good bet.
2) How to clean up your fragged system. Fragged files can take up lots of space, prevent files from
being written contiguously etc. This is just the nature of using large files and its more about maint
than prevention at this point.
Option a) use a file defrag tool. While OSX does provide some cleaning its not really efficient for your
purposes. Tools like iDefrag do a much better job of cleaning up the drives and have a couple
of nice optimizing set ups. You can run this tool from the Raid drive itself in a quick mode or,
boot into the non raid drive and defrag the raid drive volume. This approach works well.
Option b) Perhaps I should have stated before, you will need some type of backup/clone software to
back up the raid volume (3drives) to the 1.5 tb drive. There are several out there. While
Retrospect is a high end one its cumbersome. I believe SuperDuper is far less expensive and
ideal for your needs. What you can do is simply Back up your entire Raid to the 1.5 TB drive,
then boot into the 1.5 which is an exact match. If you can boot up successfully and all seems
as it should, reverse the process. - Back up the 1.5 drive onto the Raid. The wiping of your
raid drive and installing of the 1.5 drive "data" will remove pretty much all the fragged files
akin to a clean install (actually better).

Recap -
3 Drive Raid, 1 unraided drive = to the size of the Raid (1.5 tb).
If you want a partition for the OS, do it after creating the Raid.
Optimize your application(s)
Make sure both RAM and Vid Card are the right fit for your purposes
Keep the Raid volume "clean" with some regular maint (Defrag etc.)

Btw, I have a similar system and do photoshop mostly.
Quad 2.66 Mac Pro w/ 9 gigs RAM, ATI 1900 vid card
3 drives in raid, 1 drive "back up and EFI update control"
Use both a back up software and a good defrag tool.
My system seems to run pretty fast. My only "hit" is that
I use VMware Fusion and keeping that single giant file of
Windows is a pain. VMWare did offer a config to break up
that giant file into 2 gig pieces. I may try that soon <G>

Hope this is of help.
Phrehdd

^^
Thats quite the impressive first post!!!

I totally agree - excellent first post. I agree with most but differ slightly. I never have the OS on the RAIDed drive. For the cost of another card and a drive you can have a mirrored drive with your OS installed and that may help. Of course an external to run Time Machine onto is the same thing IMO.

Perhaps look at the bus speed of the Mac and the speed of the RAID card to see if they are at conflict. A slow bus speed can lose all the speed you seek. Speed is a function of money - faster drives, faster cards all cost.

Having two separate drive systems fits into the IT mentality for backup strategy - one for OS (to be locally cloned for safety) and the RAID backed up to the Network server is correct.

There are several other ways to improve upon speed but there are budget constraints that can get in the way.

Other options would include SAS, hardware raid internal and certainly hardware raid external. I think the original post somewhat implied that Corbin is trying to work with what he has. Even my response suggested a small outlay for a 1.5 gig drive and possibly a couple of pieces of software.

Of course, no mention of how much RAM is on board present a challenge in optimizing a system.

FYI - Mirroring a drive usually works the same or slower than a single drive. It does provide a safety factor and has its place. Data storage should be mirrored or in raid 5/6 setup. Active files take too great a hit with mirroring.

On mirroring, something to consider - IF* something goes wrong with software or OS, it is duplicated on the mirrored drives. In short you end up with two disks with bad systems. Mirroring is about hardware failure only. My mention of doing backups locally, is technically considered asynchronous in that it is not real time. Disadvantage being you have no immediate copy of most recent files if it should crash. Advantage, if you screw up your system or a hard drive failure, your back up drive can be fired up immediately and should be operational. So...lots to consider. : )

Fly in the ointment - if you must* work with 4 x 500. You can consider a slight boost in speed and be safe as well - make 2 sets of mirrored drives then stripe them together. This requires a lil familiarity with Apple's Disk utility. You should read up on RAID 0+1 and 1+0 first to get a feel for this. In this set up, even if 1 drive fails you can continue working with little if any slow down.

Btw, if you use the 3x500 raid (striped) and the 1.5 drive, if you do your backup to your 1.5 daily, IT can elect to back up either the 1.5 drive or the raid. It wont matter as they both have the same data. Superduper has a neat little feature that lets you do one fll back up then all future backups can be set to only back up the deltas (any changes to your raid system whether its adding/changing files or of removed files). First back up takes a while, smart update backups take far far less time. I guess I should admit I am not a fan of Time Machine for large file work. It kind of gets in the way at time but that's just my experience with it. I do have it set up for a friend of mine who loves it. He mostly works on documents so it makes sense for him.

I admit I come from the other camp - DOS-Win and at one time OS/2. I do some linux but not my forte. I went to Apple on Intel when I did some pro testing of Vista. I KNEW* it was time to leave the dark side <G>