Carson Gaspar <[EMAIL PROTECTED]> wrote:

> Louwtjie Burger wrote:
> > Dumping a large file from memory using tar to LTO yields 44 MB/s ... I 
> > suspect the CPU cannot push more since it's a single thread doing all the 
> > work.
> >
> > Dumping oracle db files from filesystem yields ~ 25 MB/s. The interesting 
> > bit (apart from it being a rather slow speed) is the fact that the speed 
> > fluctuates from the disk area.. but stays constant to the tape. I see up to 
> > 50-60 MB/s spikes over 5 seconds, while the tape continues to push it's 
> > steady 25 MB/s.
...
> Does your tape drive compress (most do)? If so, you may be seeing 
> compressible vs. uncompressible data effects.

HW Compression in the tape drive usually increases the speed of the drive.


Jörg

-- 
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