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Areca Raid Gurus.. Need advice with Raid 5 setup
My Setup:
– 5.1 MacPro with 3.4 ghz hex core/24gb 1333mhz ram/Mountain Lion 10.8.1
– Areca 1882-ix-12 firmware 1.51/Battery Backup Unit/4gb Cache
– Boot Drive – Pair of 240gb Intel 520 SSD in raid 0 connected to Areca card internal port SFF-8087
– Data Drives – 8 WD RE4 2tb drives in 14tb raid 5 with 128k stripe (all new drives with latest B01 firmware)
– Enclosure – Cineraid CR-T08E enclosure (https://www.cineraid.com/products/editpro_x_t08e.htm) and connected via 2 SFF-8088 mini-sas ports
– Mini-sas adapter – ADP-8873-2X (https://www.cs-electronics.com/mini-sas_adapters.htm) to allow second mini-sas cable to be attachedMy Problem:
When testing 8 drive raid 5 with AJA system test or Blackmagic I get reads of 630mbs and writes of 1120mbs…shouldn’t the reads be much better in a 8 drive Raid 5 setup? Here is a comparable setup: https://www.arecaus.com/areca_tests_1882x_mac_8_st33000650ns.htm I realize those test drives were 6Gb/s SATA and mine are 3Gb/s sata but I still thought I should get much better read speeds? Before I switched to the Cineraid enclosure, I had a internal 6 drive raid 5 setup (same WD drives and Areca card) with read/writes of approx 750/750 mbs…which seems appropriate for that setup. So why are my 8 drive raid 5 read numbers so SLOW?
What I’ve tried:
1. Tested same 8 drive setup in Raid 0 and saw approx 1350/1350 read/writes…so the system is capable of very fast read/writes.
2. I have tried a variety of different settings on the Areca card and nothing seems to make much difference.
3. Switched out cables.
4. Switched ports on the card.
5. Switched ports on the enclosure.
6. Contacted Cineraid and Areca tech support…still working with both to see if they have any other solutions.Any thoughts to whats leading to the slow read numbers in my raid 5 setup…I don’t think it’s a problem with the hard drives because the raid 0 numbers are right where they should be and the raid 5 writes are where they should be, it’s only the raid 5 reads that are SLOW.
Thanks in advance and sorry for the long post.
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14 Replies
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Thanks for posting this, Maris – looks like it’s an issue with the Areca card’s brain.
Areca 1882x, 8x Enterprise class HGST 7K3000 2TB 6G drives in RAID6, CineRAID CR-R16E: 996.5MB/s writes, 479MB/s reads.
(These numbers are more than fine for the client; but they do indicate that something’s not right, performance-wise. The host machine is Early 2008 xServe running model 10.6.8.)
The numbers are fairly close to yours, given that it’s RAID6, and because the drives are (a) 6G, (b) quite different from yours, (c) have been tested by Areca, this indicates an issue with Areca controller.
I will send my numbers to Areca and see what they have to say. If you have a chance to borrow an R380 or R680, I would love to see what kind of numbers you will get.
Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA -
Areca is able to duplicate the issue and are looking at it; promised to update me as soon as they have anything to report; I’ll post here once they do.
Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA -
Alex,
Thanks for the update…I’ve been in touch with Tekram tech support and they have are working on the issue. I’ll just wait and see.
Maris
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I’m am getting the same thing on a version 3.0 1882i internal 8 drive raid with 6gbs drives. Slow ramp up of speed initially and then the reads do not seem to be where they should be…about the same as what you are getting. I have not tried a RAID 0 yet though…will give that a try. Glad to know I’m not the only one with this strange issue. Keep us posted.
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Thanks guys, I see reports of slow reads with ARC-1880 series in places other than Cow, as well. Hopefully it’ll get fixed soon.
[Alex Gerulaitis] “Areca is able to duplicate the issue and are looking at it”
Did I really just write that? Good write, bad read (proofing) speeds? Thanks heavens my English teacher can’t see it. Oh wait…
Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA -
Hi guys,
I’m having similar issues with the Areca 1882x, 3 WD Caviar black 6 GB/s and Proavio unit. The read and write speed is what I expected, but the read transfer rate is not stable. I think the problem is related to the WD caviar black, since I have heard that WD set high values for the TLER for the desktop version.
Should I buy the Hitachi Deskstar or move to the WD RE4?
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Robert,
I tried 8 Hitachi 4TB Deskstar’s in a Raid 5 setup and I still had slow read speeds that were the same as my WD RE4 2TB drives. So for my setup, the problem is definitely not the hard drives, it’s got be be a controller issue. -
I attach the best configuration I’ve been able to get with the 3 WD caviar black drives.
I set TLER setting to Disabled and Read Performance Margin to 20%Still, I wil be moving to RE4 drives just because the TLER issue I read in the forums.
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Alex,
Have you heard anything from Areca on this issue of slow read speeds with Raid 5? Also, you mentioned that you have seen this issues somewhere else on the web…any idea where?
Thanks,
Maris Luters -
Not yet – will check with them again.
Here is a short list with links to a couple of other places where people report slow read speeds:
https://plus.google.com/u/0/115448387788673266686/posts/88LZvsC7ttJ
Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA
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