troubles with Areca 1882x and RAID array

[Paul Joy]

Just to keep this updated incase anybody else is reading with the same issues, here’s where I’m at now.

After testing a second 1882x adapter and moving to an OS10.7 based Mac Pro the issue persisted. We then deleted the RAID 6 volume and created two four disk RAID 5 arrays, both were slow reads.

We then deleted the RAID 5’s and created individual pass through disks and tested each drive individually within the Enclosure and average read speeds remained much lower than expected, around 50% of the write speeds. We also tried a WD Cavair drive and that performed the same.

Upon closer inspection of the read data what was actually happening was that all the drives were constantly fluctuating between very low reads below 10 MB/s and then higher speed reads around 130MB/s resulting in the average speeds of around 60 MB/s.

The supplier of the kit has asked me to return it for further investigation, I’ll keep you updated as to what happens.

Paul.

[Paul Joy]

So after having the kit for a couple of days Enhance-Tech have come up with a configuration that seems to do the trick with this set up. I’ve posted a full description on my blog along with the settings that solved the problem.

https://www.pauljoy.com/2012/08/mac-pro-raid-setup/

Thanks for all the help provided

Paul

[Alex Gerulaitis]

Paul,

Great write-up, and congrats on making it work.

The one thing I’d add to it, is for potential purchasers to consider an expander unit vs. a “dumb” box. Your current setup is “closed”, no room to add more storage unless you add another RAID controller. Getting an expander unit (about $600 more) will free up one MiniSAS port on the controller, and add two more in the back of the storage box – to which additional enclosures can be daisy-chained.

To some, this may be useful as few people ever have enough storage – with the additional benefit of getting more speed.

(While I don’t believe Enhance/ProAvio make an 8-bay 6G SAS tower expander box, the IS316JS is a 16-bay rackmount version of it, an excellent product. Other vendors do make 8-bay 6G expander boxes.)

Alex Gerulaitis
Systems Integrator
DV411 – Los Angeles, CA

[Jeremiah Belt]

Would love to hear any updates on this issue. I have a new 1882i PCIE3 on a PC. In a RAID 5 config with currently 7 WD Black Caviar 1TB 7200rpm SATA 6Gb drives (waiting an RMA on the 8th drive) attached to the card internally. I’m getting great write speeds but sporadic read speeds. The writes usually hover around 800-1000MB’s but the reads are strange….they have a slow ramp up to speed in multiple stages over a few seconds….then at speed I get readings of 650MBs or 400MBs average depending on what benchmark is used. If you look at the details its’ wildly all over the place, 2000,MBs to 3000MBs on one read then the very next reading is 140MBs or 450MBs. Sometimes dropping under the 100MBs mark. Every reading is this way ping ponging to thousands of MBs and then low hundreds every other read. Not consistant at all. Tried every setting and am at a loss. Each drive passed the WD extended Surface scan and is on the same firmware. Any help or suggestions would be great.

[Rob Curley]

I have exactly the same issue. Installed the 1882x in a 2009 MacPro/Lion and an iStoragePro 8Bay miniSAS with 3TB Ultrastars.
The Config. is RAID 6.
I get a fast spike write at 1000 MBs and read flounders a 500MBs. I’ve emailed Areca, waiting for a reply.
There seems to be alot of ppl with this issue

[Alex Gerulaitis]

The latest update is that Areca was able to replicate the issue; it’s the firmware thing; they need to figure out what’s causing the problem and then roll out an update.

Not time frame yet.

Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA

[Paul Joy]

I posted a resolution to my problem but it’s in the wrong place in the reply list, check my blog post and see if that helps you at all.

https://www.pauljoy.com/2012/08/mac-pro-raid-setup/

[Roberto Munoz]

Hi guys,

I also have an Areca 1882x, Proavio Editbox 8 and 3 WD caviar black 2 TB disks. I run AJA, and the system peaks at 360 MB/s, but it’s intermittent and ca go down to 250 MB/s. I updated the firmware, followed Paul Joy’s advices, but still no solution to the problem.

I’m using the WD caviar black as a test, but then I would like to fill the entire rack. Should I buy another set of drives?

Thanks in advance.

[Alex Gerulaitis]

[Paul Joy] “I posted a resolution to my problem but it’s in the wrong place in the reply list, check my blog post and see if that helps you at all.”

Paul,

The solution was to return the array, have the vendor tinker with it and return back to you fixed? I couldn’t find anything else resembling a solution on your page.

[Alex Gerulaitis]

[Roberto Munoz] “I’m using the WD caviar black as a test, but then I would like to fill the entire rack. Should I buy another set of drives?”

Certainly, except not the Black Caviars – they’re not qualified for parity RAIDs. I’d look at HGST 7K4000 or 7K3000. The enterprise class versions (Ultrastars) are the only drives out there with both a 2m hrs MTBF and a 5-year warranty.

Alex Gerulaitis
Systems Engineer
DV411 – Los Angeles, CA