DragonFly users List (threaded) for 2005-09
Re: UFS filesystem size limit
:For reference, I'm using:
:# uname -sv
:DragonFly DragonFly 1.3-Preview #0: Fri Jul 8 14:09:49 CEST 2005
:I have created a vinum partition that is 1.12 terabytes. As some of
:you may expect, /sbin/newfs is not happy with this size (# sectors in
:partition > max value for a signed 32 bit integer).
:Is there any current way to get a filesystem past the terabyte limit?
:Dave Hayes - Consultant - Altadena CA, USA - dave@xxxxxxxxxxx
:>>> The opinions expressed above are entirely my own <<<
:Only one who is seeking certainty can be uncertain.
There are a number of limits that effectively make it 1TB due
to the block representation for device I/O (2^31 x 512). There
is also a theoretical UFS1 limit of (2^31 x fs_block_size)
which implies e.g. (2^31 x 8192) = 16TB (more if you use a
larger block size), but there are probably still internal
overflows in UFS1 that effectively make that limit 1TB too.
Hiten has been working on the BUF/BIO subsystem. He and I have
been going through bunches of patch sets but I really doubt
that we will have a 64-bit clean I/O path by the next release.
At the moment we are simply working to separate the b_lblkno/
b_blkno/b_pblkno mess and to introduce a layer that we will
be able to use to implement I/O scheduling.
FreeBSD's UFS2 can do larger filesystems now, but you would have
to inquire on the FreeBSD lists as to the stability.