SAS drives worth the price?

[semper]

I'm planning to buy a Mac Pro to replace my 4-year-old Dual G5.
I hope to use the new machine for at least that long, so I'd like
a configuration that will give me a reasonable performance for
the next few years..

My planned configuration so far is:

8-core 2.8 (or 3.0?)
8GB of memory (I have 3.5 now, which is a bit low)
GeForce 8800 GT

I'm not sure about the hard drive configuration. I'm thinking
about going with the lower processor speed, but investing
a bit in HD performance.

Is the performance of the SAS drives worth the price (rather
expensive HD plus the RAID controller)? Is it possible to
have 1 or two SAS drives (for the system and frequently used data)
and some large SATA drives (for the bulk data) in one system?

Currently I use my machine for Aperture, digitizing and OCRing
documents, Java development and running stuff like
tiles@home (rendering map tiles for the openstreetmap.org
project).

 

[Cromulent]

The SAS drives are only an option if you purchase the RAID card as well so bear that in mind.

They are worth it if you require extremely fast hard drive access. Most people don't require it but would like it anyway. I guess it comes down to how good your bank balance is.

From the sound of it, SAS would be a waste on your system.

I'm planning to buy a Mac Pro to replace my 4-year-old Dual G5.
I hope to use the new machine for at least that long, so I'd like
a configuration that will give me a reasonable performance for
the next few years..

My planned configuration so far is:

8-core 2.8 (or 3.0?)
8GB of memory (I have 3.5 now, which is a bit low)
GeForce 8800 GT

I'm not sure about the hard drive configuration. I'm thinking
about going with the lower processor speed, but investing
a bit in HD performance.

Is the performance of the SAS drives worth the price (rather
expensive HD plus the RAID controller)? Is it possible to
have 1 or two SAS drives (for the system and frequently used data)
and some large SATA drives (for the bulk data) in one system?

Currently I use my machine for Aperture, digitizing and OCRing
documents, Java development and running stuff like
tiles@home (rendering map tiles for the openstreetmap.org
project).

 

[yeroen]

SAS drives are fast but you pay the following penalties with the Mac Pro:

1) $$$$$ - expensive drives require expensive BTO raid card
2) somewhat limited capacity (relative to the 750GB/1TB SATA drives)
3) You can't mix and match SATA and SAS drives in one system

The 15K RPM SAS drives are really optimized for a multi-user server environment usage pattern where you have lots of successive, unrelated, random accesses. The fast seek time of the 15K RPM SAS drives really help in this situation.

Otherwise, for a single-user workstation you don't really need it. For example, if you're working with Aperture, then what you really need is large storage space for all those RAW and PSD files. Keep in mind also, that large 7200RPM drives, due to their higher platter density, have very high sequential read/write transfer rates; higher that the 10K raptors and competitive with 15K SAS drives. This is good news if your I/O usage pattern has high spatial locality (i.e. accessing and manipulating image files, media files, etc.), and since this is what you'll be doing, I'd recommend stocking your Mac Pro with high capacity, high density SATA drives.

 

[semper]

3) You can't mix and match SATA and SAS drives in one system

The 15K RPM SAS drives are really optimized for a multi-user server environment usage pattern where you have lots of successive, unrelated, random accesses. The fast seek time of the 15K RPM SAS drives really help in this situation.

Thanks, that makes the decision easier (and cheaper, too)