UFS2 max limits?

John-Mark Gurney gurney_j at resnet.uoregon.edu
Tue Nov 15 00:22:57 GMT 2005

Attila Nagy wrote this message on Sun, Nov 13, 2005 at 18:51 +0100:
> Joseph Koshy wrote:
> >The Wikipedia page referenced below says that UFS2 supports a
> >filesystem size of 2^80 Bytes (1YiB) with the limit on a given
> >file being 2^55 bytes (32 PiB).
> >Are these numbers correct?  I somehow remember the limits as
> >being much lower (of the order of 16TB or so).
> I could only create a 128TB sparse file on an UFS2 partition, so I guess 
> 32 PB is a little bith high.

No, it is not...  The reason you were limited to 128TB is that you did
not create your filesystem with -f 65536 -b 65536...  If you look at
my equation that I posted earlier, if you have a blocksize of 16384,
you end up with ~128TB as the max file size...

		    K	   M	  G	 T
(16384/8)^3*16384 / 1024 / 1024 / 1024 / 1024 == 128

  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."

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