To RAID or not to RAID

[julian]

Hi,

I am about to format an external SATA enclosure for future use with VI and as a scratch disc for Logic's audio files. It makes sense for me to use the same discs for both because as the number of audio files increase (real instruments) the VI use would decrease and vice versa.

On the audio files side it is a no brainer for me to RAID 0 the discs via a SATA 2 PCIx controller (x4 Western Digital 4000KD's - 16Mb cache) this would give me a real life throughput of 200MB/second plus - 4 times the Mac G5's internal disc. I have additional discs for constant file back-ups so the reliability factor of using RAID 0 is not an issue here.

However Christian, in an answer to another thread "SATA Quad Hard Drive", expressed reservations about certain RAID set-ups (I'd be using Disc Utility so make a soft raid 0 ) hinting their performance might be worse than individual discs when the main purpose is streaming lots of small sections of files.

Given that a RAID 0 will give me huge performance increases for my Logic audio files - and I'm frequently hitting the limits of "disc too slow" will I not get so good a performance with the VSL VI compared with the 4 discs as JBOD.

Finally, as Herb has indicated that the number of files running the full Symphonic Cube is reduced to about a thousand, I guess it will be best to format the discs with the maximum sector size (in my case 256k).

Thanks for any advice,

Julian

[julian]

Any thoughts...

Christian ?
Dietz ?

thanks

Julian

[JWL]

julian--

I've been patiently watching this thread for over a wekk now. I, too, am curious.

Just recently saw a demo by the VSL team in Los Angeles, and someone almost casually mentioned the Apple X-Serve Raid as an option, but no one expounded on the topic.
http://www.apple.com/xserve/raid/

The G5 Drive Bracket was another option I was considering-- supports up to five internal SATA's in one G5.
http://www.amug.org/amug-web/html/amug/reviews/articles/g5bracket/

I wish I had a definitive answer for you, but I can only join you in the quest for the "grail" setup.

Here are some links to other threads which may help...

Hard Drive Thoughts
http://community.vsl.co.at/viewtopic.php?t=5667&highlight=multiple+sata

G-Tech Drives
http://community.vsl.co.at/viewtopic.php?t=6423&highlight=multiple+sata

Apple RAID
http://community.vsl.co.at/viewtopic.php?t=4861&highlight=multiple+sata

[julian]

I tried a set up from sonnet - their G5 Jive that provides 3 extra internal SATA drives to make a total of 5 in a G5. There were issues though. Firstly if all drives are powered up at the same time the Macs power supply trips. The only way round this is to get controlled spin up working on the drives and spin them up sequentially. Currently this was not possible to do.

Also when I got all 5 drives on at the same time by manually connecting the power cables! - the fans in the G5 stepped up their speed to compensate for the extra loads/heat. In conclusion i'm not sure this way could be recommended.

I am now using a 4 bay external enclosure from transint (MiniG) with 4 drives. I had been using them as 4 seperate drives but last week raided them all together as a raid 0. There has been an immediate jump in performance in both the load up times of songs using large VSL set-ups and the number of voices that can be used before the system gives up! Also by adjusting the EXS sampler in Logic to accomodate higher disc performance smaller amounts of sample start are loaded for the streaming - this increases the number/size of VSL instruments that can be loaded into RAM.

Julian.

[JWL]

Great, Julian. Thanks for the tips. E-SATA seems to be the way to go at this time. Congrats on your speed boosts!

best,
jwl