Really Slow Preclear

[Plimsoul]

Started to preclear 3 drives (2TB Hitachi & two 2TB WD20EARS) at the same time.  The Hitachi and one of the EARS seem to be progressing nicely, but the other EARS is really, really slow.  We're talkling 12 MB/s on Step 2.

 

I'm thinking this isn't normal.

 

This is a new build with the Sempron 140 and the drives housed in the Supermicro 5-in-3 rack.  I did jumper the EARS drives before installation.

 

Is there anything I can do to diagnose this before the preclear script finishes?

 

Thanks

[lionelhutz]

Posting or at least looking through the syslog would be a good idea. It sounds like a drive problem or a connection problem.

 

Peter

 

[vca]

Started to preclear 3 drives (2TB Hitachi & two 2TB WD20EARS) at the same time.  The Hitachi and one of the EARS seem to be progressing nicely, but the other EARS is really, really slow.  We're talkling 12 MB/s on Step 2.

 

I'm thinking this isn't normal.

 

This is a new build with the Sempron 140 and the drives housed in the Supermicro 5-in-3 rack.  I did jumper the EARS drives before installation.

 

Is there anything I can do to diagnose this before the preclear script finishes?

 

Thanks

 

I think that I might have run into a similar problem, see this post:

 

http://lime-technology.com/forum/index.php?topic=10166.msg96818#msg96818

 

My solution was to return the drive, the replacement (same model) performed properly.  There were no indications of problems in either the SMART report or the syslog.

 

Stephen

[Plimsoul]

Well, I aborted the first preclear while it was still writing 36 hours later at about 10MB/s. Then took out the other drives and moved this guy to a slot in the rack that successfully supported another drive's preclear.  Started another preclear session and now, 23 hours later, it is only 24% done with the Disk Pre-Read at 3.5 MB/s.

 

Guess it is back to Newegg with this one!

 

The syslog and SMART reports don't seem to show any obvious problem.

[SSD]

Well, I aborted the first preclear while it was still writing 36 hours later at about 10MB/s. Then took out the other drives and moved this guy to a slot in the rack that successfully supported another drive's preclear.  Started another preclear session and now, 23 hours later, it is only 24% done with the Disk Pre-Read at 3.5 MB/s.

 

Guess it is back to Newegg with this one!

 

The syslog and SMART reports don't seem to show any obvious problem.

 

I had a disk fail this weekend.  Nothing obvious wrong in preclear, but running about 80 MB/sec which was slower than the 100 MB/sec I was expecting, but not aweful.  But the drive gave itself away by spewing a ton of nasty log messages in the unRAID syslog.  Pulled the drive and replaced with identical one.  Precleared 100% perfect.  I even swapeed back in the first one to double check and ton of errors again. RMA.

 

Not all drives fail in the same, boring predictable way!

[Joe L.]

Well, I aborted the first preclear while it was still writing 36 hours later at about 10MB/s. Then took out the other drives and moved this guy to a slot in the rack that successfully supported another drive's preclear.  Started another preclear session and now, 23 hours later, it is only 24% done with the Disk Pre-Read at 3.5 MB/s.

 

Guess it is back to Newegg with this one!

 

The syslog and SMART reports don't seem to show any obvious problem.

I wish it was as clear-cut to figure out what is happening when a drive has issues...  (might be the drive, might be the cabling, might be the disk-controller, might be a overloaded power supply... all might cause a problem)

 

At least the pre-clear script allows you to know of some of the issues you might see before you assign the drive to your array. 

 

Joe L.