I need UFS stress tool which produce file open, creation.

does anyone aware of such tool for Solaris?

-Udi

On Thu, 2007-07-12 at 13:00 -0700, Darren Dunham wrote:
> > We use ufsdump to backup our file systems to 8 mm,
> > 4mm or DAT 72 tape drives. The default blocking
> > factor ufsdump uses is 64 (without b or c option) and
> > the problem with this is the amount of data that can
> > fit on a tape because of the IRG.
> 
> Does the IRG really cause a substantial difference in the capacity?
> 
> > My questions are:
> > 
> > - how can I find out the optimum blocking factor (or
> > that is supported) for each tape device
> > (8mm/4mm/DAT72)?
> 
> I would suppose you'd just go as high as you can if you're trying to optimize 
> for space.
> 
> > - what are the issues of changing the blocking factor
> > to 512 (ufsdump code seems to cap the blocking factor
> > to 512)?
> 
> Older operating systems might not be able to deal with very large factors.  A 
> factor of 126 was commonly used because some old OS's broke at 128.  I don't 
> know if anything has a problem there now.
> 
> For smaller tapes or smaller files on tape, you're wasting space in the final 
> block because it is likely that more of it will be unused with a large block 
> size.
> 
> Also 'ufsdump' and the tape have their own blocks.  I imagine it's setting 
> them to be the same, but I haven't tried to confirm that.  You could reblock 
> with 'dd' or something even if the ufsdump code were limiting.
> 
> ufsdump 0f - /source | dd of=/path/to/tape obs=<blocksize>
> 
> You'd probably need to reverse that on restoration, because ufsrestore isn't 
> going to know to use a larger blocksize for reading (you'll get an "out of 
> space" error).
> 

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