SATA RAID0 vs SCSI

[Pat]

The motherboard on my workstation has both SATA and SCSI (LSI Ultra-320)
controllers and supports RAID0 with SATA drives. I was wondering which
would be better with regard to

1. performance
2. acoustics (quiet operation)
3. reliability

two SATA-300 drives in RAID0 or one 15krpm SCSI drive?

Thanks for any opinions/advice.

Pat

 

[Peter]

The motherboard on my workstation has both SATA and SCSI (LSI Ultra-320)

controllers and supports RAID0 with SATA drives. I was wondering which
would be better with regard to

1. performance

Depends for what application; database or streaming have different
requirements.

2. acoustics (quiet operation)

15K Rpm drives are noisier than 7200 Rpm.

3. reliability

Single SCSI will be more reliable that SATA in RAID0. But you still need to
protect your data.

two SATA-300 drives in RAID0 or one 15krpm SCSI drive?

Thanks for any opinions/advice.

Pat

Your motherboard SATA RAID0 might still be poorly implemented. Depends on
motherboard.

 

[Pat]

Depends for what application; database or streaming have different
requirements.

I was thinking mostly in terms of opening/closing applications, which could
include large CAD files. I also run FEA (finite element analysis) codes
occassionally, which (for larger models) sometimes involves virtual memory
access.

15K Rpm drives are noisier than 7200 Rpm.

Makes sense. Right now I have a single SATA drive installed, and the only
thing I hear are the system fans. Do you think I would like likely hear the
SCSI drive over fan noise (which really isn't too bad)?

Single SCSI will be more reliable that SATA in RAID0. But you still need
to protect your data.

Makes sense also (two possible points of failure).

Your motherboard SATA RAID0 might still be poorly implemented. Depends on
motherboard.

The workstation is a HP xw9300 (dual Opteron) but I'm not sure if HP makes
the motherboard or not. According to the manual, the SATA RAID controller
is made by NVIDIA. I also discovered that the LSI SCSI controller supports
RAID as well (I'm guessing the noise of this setup would be pretty bad
though).

Thanks for the feedback.

Pat

 

[Arno Wagner]

The motherboard on my workstation has both SATA and SCSI (LSI Ultra-320)
controllers and supports RAID0 with SATA drives. I was wondering which
would be better with regard to

1. performance

SCSI. Unless it is raw linear read/write performance you look for.
Then it should be a close draw.

2. acoustics (quiet operation)

Depends on the disks.

3. reliability

Definitely SCSI by a large margin, given that RAID0 is
half as reliable as the individual disks and SCSI disks
are still a lot more reliable than consumer grade disks.

Arno

 

[Arno Wagner]

I was thinking mostly in terms of opening/closing applications, which could
include large CAD files. I also run FEA (finite element analysis) codes
occassionally, which (for larger models) sometimes involves virtual memory
access.

Swapping will be faster on the SCSI disk. May be a factor of 2 or
even higher.

Makes sense. Right now I have a single SATA drive installed, and the only
thing I hear are the system fans. Do you think I would like likely hear the
SCSI drive over fan noise (which really isn't too bad)?

Depends on the SCSI drive. THrere are quite ones out there, though not
all are quiet.

[...]

Arno

 

[Recrea]

The motherboard on my workstation has both SATA and SCSI (LSI Ultra-320)
controllers and supports RAID0 with SATA drives. I was wondering which
would be better with regard to

1. performance
2. acoustics (quiet operation)
3. reliability

two SATA-300 drives in RAID0 or one 15krpm SCSI drive?

Thanks for any opinions/advice.

Pat

1 and 3: SCSI

2. Don't know about U-320, but my ol' IBM Ultrastars (68-pin U2W) sure are
loud compared to this new Samsung (PATA/EIDE) drive I just got. I didn't
realize, until now, how loud they actually are. I can't even hear the
Samsung over the fans. (Might've gone deaf by the Ultrastars.)

and, then #4....

4. The wallet. Definetly not SCSI. Been on that road before, getting the
newest/greatest SCSI. That'll thin the wallet in a hurry.

 

[timeOday]

SCSI. Unless it is raw linear read/write performance you look for.
Then it should be a close draw.

Not even close.

A single 15k scsi drive is about 80 MB/s
<http://www.tomshardware.com/2003/11/19/elitists_on_the_test_bench/page10.html>

A pair of SATA raptors sustain 140 MB/s
<http://www.gamepc.com/labs/view_content.asp?id=eoyraid&page=10>

To the original poster, this article might also interest you:
<http://www.tomshardware.com/2006/02/06/wd1500ad_raptor_xtends_performance_lead/index.html>
They compare the Raptor 10K SATA to a SATA Raid-0 and the Raptor wins
except in sustained read/writes.

 

[Eric Gisin]

Arno Wagner wrote:

Not even close.

Very close.

A single 15k scsi drive is about 80 MB/s
<http://www.tomshardware.com/2003/11/19/elitists_on_the_test_bench/page10.html>

Ancient technology. More like 120MB for the Cheetah 15K.5.

A pair of SATA raptors sustain 140 MB/s
<http://www.gamepc.com/labs/view_content.asp?id=eoyraid&page=10>

To the original poster, this article might also interest you:
<http://www.tomshardware.com/2006/02/06/wd1500ad_raptor_xtends_performance_lead/index.html>
They compare the Raptor 10K SATA to a SATA Raid-0 and the Raptor wins
except in sustained read/writes.

You contradict your previous position.

 

[Arno Wagner]

Not even close.

A single 15k scsi drive is about 80 MB/s
<http://www.tomshardware.com/2003/11/19/elitists_on_the_test_bench/page10.html>

A pair of SATA raptors sustain 140 MB/s
<http://www.gamepc.com/labs/view_content.asp?id=eoyraid&page=10>

Over an PCI bus that can (theroetically) sustain 135MB/s?

Arno

 

[timeOday]

Very close.

Ancient technology. More like 120MB for the Cheetah 15K.5.

That drive was just announced a few days ago and it's claimed to be a
full 30% faster than its predecessor in sustained transfers. I wasn't
even able to find any benchmarks on it yet. But it sounds like the
situation will now be closer than it was before.

You contradict your previous position.

I only said that Raid-0 is king for sustained IO, not that it's best
all-around.

 

[Peter]

The motherboard on my workstation has both SATA and SCSI (LSI Ultra-320)

Over an PCI bus that can (theroetically) sustain 135MB/s?

Arno

Nvidia nForce Professional 2200 attached SATA drives are not limited by PCI
32bit/33MHz bus!!!

 

[J. Clarke]

Over an PCI bus that can (theroetically) sustain 135MB/s?

Looking at the article, they tested an AMCC 9500 (64-bit/66MHz PCI), the
Intel 6300ESB and ICH6R, both of which are implemented on the Intel
Integrated Controller Hub and not attached to the PCI bus at all, the
nvidia nForce4 VRaid, which is also not on the PCI bus, Promise PDC20579
(32-bit 66MHz), SI3114 (32-bit 66MHz), and the Via 8237R v-raid, which also
doesn't have the the RAID controller on the PCI bus.

So, the 135MB/sec PCI bus is not really an issue for any of them except
possibly the Promise PDC20378 for which I couldn't find any data.

 

[Pat]

That drive was just announced a few days ago and it's claimed to be a full
30% faster than its predecessor in sustained transfers. I wasn't even
able to find any benchmarks on it yet. But it sounds like the situation
will now be closer than it was before.


I only said that Raid-0 is king for sustained IO, not that it's best
all-around.

Thanks for the feedback and links.

It seems to me that if the HD is only used by a single user, then having
high sustained IO would be better (as opposed to, say, a file server
application where many users could be trying to access the HD
simultaneously, requiring the HD to jump around to gather that data - there
I imagine SCSI would win). Is that right?

Also, with regard to the WD Raptor, what advantage would it have over a
10krpm SCSI (assuming one had both SATA and SCSI controllers available)?
Less expensive or quieter?

 

[Folkert Rienstra]

Over an PCI bus that can (theroetically) sustain 135MB/s?

Did you loose a massive amount of braincells over the weekend, arnie?

Serves you right, with that alcohol abuse of yours.

 

[timeOday]

Thanks for the feedback and links.

It seems to me that if the HD is only used by a single user, then having
high sustained IO would be better (as opposed to, say, a file server
application where many users could be trying to access the HD
simultaneously, requiring the HD to jump around to gather that data - there
I imagine SCSI would win). Is that right?

Well, not really. Many different files are accessed in launching even a
single application. These files tend to be relatively small, so the
access (or seek) time is important.

If you are short on RAM and use virtual memory at all, that will also
require fast seek time. Though if that's the case, you should be buying
more RAM instead of RAID or SCSI anyways.

Sustained IO only really dominates when dealing with very large files.
If you are doing high bitrate (uncompressed) video capture, for
instance. Or copying big video files.

Also, with regard to the WD Raptor, what advantage would it have over a
10krpm SCSI (assuming one had both SATA and SCSI controllers available)?
Less expensive or quieter?

Mainly the price. But the perfromance of a 10K RPM SATA drive will be
very close to the performance of a 10K RPM SCSI drive, especially for a
single user.

There is always the hope of higher quality/reliability with SCSI drives,
simply because they are built to a higher price point. This may well
be true on average, but there seems to be so much variance within models
and even individual drives that the picture is not clear. Our
SCSI-based RAID servers certainly seem to have their share of drive
failures.