jademonkee

New HP MicroServer gen8 w/ 2x 4TB - 33MB/s building parity normal?

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Sorry i cant remember the bios settings or options on the micro gen 8.

But just make sure no disk controllers are in raid mode as unraid needs direct access to the disks. But seeing as you have selected sata ahci it should be ok. Maybe my speeds were faster as i had changed the cpu from the dual core celeron to a quad xeon. The slower parity could be down to the calculations needed for parity, but im not sure. Someone else here would know better than me if parity speed needs much cpu.

 

Once you have your build running if you dont already have one i would suggest using a small ssd cache drive. That makes a big difference on general use for write speeds. I put mine where the sata dvd drive goes so i didnt have to use one of the main drive bays.

If i remember i had to make up a cable adaptor for the power socket on the dvd drive power cable.

 

Thanks for your help.

I'm reckon it was just some weird thing going on with the Seagate NAS Disk firmware during the intial parity. Write speeds are fine now.

I have an SSD coming in the mail :)

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Check your system log and see if one or more of your drives are connecting as if they were an IDE drive rather than at SATA speeds.  I had the same problem when I connected my HGST NAS drives to my N54L and I could see one drive at IDE speeds.  With standard desktop Seagate drives they connected at full SATA speeds and all slots full of drives.  I thought it was an incompatibility with HGST but now it may just be the NAS function like you were speculating about.

 

 

Here were my symptoms:

I had a IBM M1015 controller installed in my N54L and when I switched the HGST NAS drives all to the M1015 the speeds returned to normal.  But no matter what drive I attached to the built in controller on the N54L (and in any slot it didn't matter which) the last drive was always at IDE speeds.  I.E. with one drive that drive was IDE speed. With two drives on the N54L controller and the drive in slot 2, 3 or 4 (didn't matter which slot or drive) it would connect at IDE speeds and the drive in slot 1 would be at SATA speeds.  Swap drives around and slots and still last drive at IDE speeds.  Add a third drive and it became the IDE Speed drive and the other two would be at full SATA speeds.  Etc...

 

Was there ever a solution to this? Or did you have to return the NAS drives?

Also, I'm not sure what to search for in the logs? I searched for "ide" but found no instances.

I'm not sure that's the problem, anyway, as I ran diskspeed and got the following results:

/dev/sdb (Disk 2): 173 MB/sec avg

/dev/sdc (Disk 1): 159 MB/sec avg

 

I'm currently copying across the network at about 80MB/s (large files).

No I just merged my N40L and N54L into a Norco 4224 case and a Rack.  Also added my other unRAID servers to the Rack as well.  My 2 N54Ls and 1 N40L are not currently in service.

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Just to follow up on this, I started a parity build on my Gen8 and it was running at about 39MB/sec.

 

I booted in to the BIOS and switched on the disk write cache and restarted the parity build. It's now running at 185MB/sec.

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Hi, any follow up's on this? I just bought a gen8 microserver and was wondering if it is safe to use disk write cache?

Have you have any problems? on the web they say it can cause corruption in case power is lost.

I was preclearing a drive and write speed was 40 MB/s, canceled it and enabled disk write cache, and now write speed is 185 MB/s (Seagate ST4000DM000)

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30 minutes ago, napalmd said:

on the web they say it can cause corruption in case power is lost.

 

Same risk as any computer without a UPS.

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Enbling drive cache fixed my slow pre-clear problems. I've had no problems with having it enabled.

I also purchased a UPS, though, as I don't want to risk data corruption. 

Note that, as johnnie.black said, you still run the risk of data corruption in the event of power loss even without drive cache enabled, so you should really by yourself a UPS anyway.

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