Question on shredding a terebyte drive

[Mikkel L. Ellertson]

Dean S. Messing wrote:
> 
> Thanks Rick.  It's in "D" state only about 5-10% of the time.  Yet
> disk writes are occuring (according to the spikes and numbers in
> gkrellm) for 1 second or so, every 2 seconds.  So that either points
> to random number computation or the wait needed to let the new
> magnetic orientation 'set'. Not sure.
> 
> Dean
> 
I would expect it to be write buffering. It may be the time it takes
to fill the write buffers, and then write them to disk, and/or write
buffering on the drive.

I know how to turn off write buffering on a mounted partition, but
not when writing directly to a drive. You can probably turn off
drive write buffering using hdparm.

You may be able to improve the time by tweaking the size of the
writes to the drive. Take a look at the "USB I/O performance" thread.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

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