Ocfs2 users - Jul 2004 - Maximum and minimum OCFS2 volume sizes?

Just a quick question.  What is the maximum and minimum volume sizes
that OCFS2 supports?

I'm working on doing a plugin for EVMS to support OCFS2.  One of the
functions needs that info.

Thanks,
John

min is a hard number to pin down as it depends on the number of nodes.
for e.g, each node eats up 8M for the journal file. then there are the
other system files + root dir.

max is kernel dependent. in 2.4, it should be (4G * blocksize).

On Mon, 2004-07-26 at 16:53, Villalovos, John L wrote:
> Just a quick question.  What is the maximum and minimum volume sizes
> that OCFS2 supports?
> 
> I'm working on doing a plugin for EVMS to support OCFS2.  One of the
> functions needs that info.
> 
> Thanks,
> John
> _______________________________________________
> Ocfs2-users mailing list
> Ocfs2-users@oss.oracle.com
> http://oss.oracle.com/mailman/listinfo/ocfs2-users

On Mon, Jul 26, 2004 at 04:53:32PM -0700, Villalovos, John L
wrote:
> Just a quick question.  What is the maximum and minimum volume sizes
> that OCFS2 supports?
> 
> I'm working on doing a plugin for EVMS to support OCFS2.  One of the
> functions needs that info.
	OCFS2 counts clusters via a u32.  So, you have UINT32_MAX
clusters as the maximum volume size.  Multiply that by the size of the
cluster (OCFS2 can be formatted with clustersizes of 4K-1M by powers of
2).  OCFS2 files have the same size limitation.
	As far as the minimum goes, the filesystem needs enough clusters
to describe itself and set up the system inodes (inodes for internal
filesystem accounting, the journals, etc).  I'd say that's on the order
of 5000 clusters, but I could be wrong.  I've successfully created a 20M
filesystem with 512B blocksize and 4K clustersize.

Joel

-- 

Life's Little Instruction Book #511

	"Call your mother."

Joel Becker
Senior Member of Technical Staff
Oracle Corporation
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127

joel.becker@oracle.com wrote:
> On Mon, Jul 26, 2004 at 04:53:32PM -0700, Villalovos, John L wrote:
>> Just a quick question.  What is the maximum and minimum volume sizes
>> that OCFS2 supports? 
>> 
>> I'm working on doing a plugin for EVMS to support OCFS2.  One of
the
>> functions needs that info.
> 
> 	OCFS2 counts clusters via a u32.  So, you have UINT32_MAX
> clusters as the maximum volume size.  Multiply that by the size of the
> cluster (OCFS2 can be formatted with clustersizes of 4K-1M by
> powers of
> 2).  OCFS2 files have the same size limitation.
> 	As far as the minimum goes, the filesystem needs enough clusters
> to describe itself and set up the system inodes (inodes for internal
> filesystem accounting, the journals, etc).  I'd say that's on
> the order
> of 5000 clusters, but I could be wrong.  I've successfully
> created a 20M
> filesystem with 512B blocksize and 4K clustersize.
Thanks for the info everyone.  I will see what I can figure out :)

John