Preclear Running VERY Slow (11 MB/s)?

March 6, 201214 yr

Been trying to preclear two drives. The first is a 750 GB WD7500AKS, the second a 2 TB Seagate ST2000DL003. The WD has successfully precleared 3 times at a rate of ~90 MB/s. The Seagate operation was terminated twice somehow mid process. It had been humming along at a similar rate. The third time I ran preclear on the Seagate it is running at 11 MB/s. Been running for 21+ hours and it's only 38% through the first pre-read.

I don't know how the first two preclear processes were terminated (something about a remote host?), but it appears they've caused this slowdown. Any advice on how to approach this? I've not had any problem with this drive to date. Is there a proper way to get the drive back on track speed wise?

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March 6, 201214 yr

Been trying to preclear two drives. The first is a 750 GB WD7500AKS, the second a 2 TB Seagate ST2000DL003. The WD has successfully precleared 3 times at a rate of ~90 MB/s. The Seagate operation was terminated twice somehow mid process. It had been humming along at a similar rate. The third time I ran preclear on the Seagate it is running at 11 MB/s. Been running for 21+ hours and it's only 38% through the first pre-read.

I don't know how the first two preclear processes were terminated (something about a remote host?), but it appears they've caused this slowdown. Any advice on how to approach this? I've not had any problem with this drive to date. Is there a proper way to get the drive back on track speed wise?

My car makes a funny noise... It is a Toyota. My old car did not make any noise... What do you think might be the cause? It used to run OK and I've taken it on several trips.

I've given you almost as much information as you've given me.

Usually a slowdown is accompanied by clues written to the system log. Have you considered looking there?

The pre-clear will terminate if run via telnet and the telnet session terminates. It is why the use of either the system console or the "screen" virtual screen manager is suggested.

Look here: http://lime-technology.com/forum/index.php?topic=9880.0

Joe L.

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March 6, 201214 yr

Author

Sorry for the lack of information, I'm still new to this. Syslog is attached. I was running preclear via Mac OS Terminal > telnet & screen when the process was terminated both times. Neither time did I exit telnet or terminal.

The Syslog shows one of the preclear processes on the Seagate was actually successful, interestingly. I don't see any errors or minor issues that stand out, but I'm still a newb and trying to learn. There is only one instance of preclear on the Seagate listed, however, I started the Seagate & the WD simultaneously each time.

syslog-2012-03-06.txt.zip

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March 6, 201214 yr

The seagate seemed to have been pre-cleared just fine. I see no evidence of any processes being killed.

Do you have a pre-clear running now? Is it possible you have two running on the same disk at the same time?

(That would slow it to a crawl)

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: ========================================================================1.13

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: == invoked as: ./preclear_disk.sh -A /dev/sdd

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: == WDC WD7500AAKS-00RBA0 WD-WCAPT0072817

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: == Disk /dev/sdd has been successfully precleared

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: == with a starting sector of 64

Mar 4 02:10:43 Tower preclear_disk-diff[30574]: == Ran 1 cycle