X-bit labs

Started by: Laglorden | Date 02/06/04

Comments: 9 | Last Comment:  03/09/04

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1. Isn't the performance in http://www.xbitlabs.com/images/storage/3ware-8500/sr-1.gif limited by the PCI-bus? If you had 8 drives the top speed would be the same? Shouldn't that be pointed out?

We didn't have 8 HDDs at that moment. But it seems impossible to achieve read speed beyond 190MB/sec with 3ware 8500 controller.

2. Hello,

Good stuff,
but has I'm not a specialist about raid array I would have greatly appreciate a reminder (or a link to an article published longed ago on your site) about what raid 5 and 10 are. I think I can guess at least(10 = 1+0) but I'm not pretty sure. Reminder would have been valuable.

PMA

Check out this article: http://www.xbitlabs.com/articles/storage/display/ata100raid-roundup.html

I hope this helps.

yes
RAID10 = RAID1+0

3. What is the CPU utilization like ? That's a key point for servers, and traditionnaly SCSI's forte .

like SCSI :)

3Ware8500 - true hardware RAID controller with onboard XOR processor.
It's use DMA Access to memory & CPU Utilization is smallest.

4. How about testing the RAIDcore 4452/4852 SATA controllers.

5. Why is the review so geared towards performance? I would have thought anyone looking for outright performace would just go for a RAID 0, RAID 1 or RAID 0+1
depending on requirements. That saves the cost of the hardware XOR engine, which is only required for RAID 5.

I am looking for something like this because of the increased data security for not much cost offered by (S)ATA RAID 5 solutions. Did you try:

o Pulling the power on one of the disks.
o Pulling the data connector on one of the disks.
o Mounting one of the disks in another system, and deliberatly corrupting it.
o Trying out the hot-swap facility.

If so, did the RAID system keep working as promised?

How about rebuild times when replacing a faulty disk? Or the impact on performance when a rebuild is in progress? If I remote-boot the system and a disk fails, does it come up anyway, or does it it sit at the card's BIOS waiting for input?

This of course should be trying with all the different OSes supported :)

Finding performance reviews on the 'net for RAID cards is easy, finding reviews on how well they protect your data is a lot harder.

(Of course, when all is said and done, there is no replacement for regular backups, but how much would that cost for a terabyte array?)

Inquirering minds need to know,

Twirlip

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