Re: [RFC 0/13] extents and 48bit ext3

Stephen C. Tweedie wrote:
> Hi,
> 
> On Fri, 2006-06-09 at 17:49 -0400, Jeff Garzik wrote:
> 
>>>> Consider a blkdev of size S1.  Using LVM we increase that value under 
>>>> the hood to size S2, where S2 > S1.  We perform an online resize from 
>>>> size S1 to S2.  The size and alignment of any new groups added will 
>>>> different from the non-resize case, where mke2fs was run directly on a 
>>>> blkdev of size S2.
>>> No, they won't.  We simply grow the last block group in the filesystem
>>> up to the size where we'd naturally add another block group anyway; and
>>> then, we add another block group exactly where it would have been on a
>>> fresh mkfs.
>> Yes but the inodes per group etc. would differ.
> 
> No, we add the same number of inodes in the new groups that all the
> previous groups have.

Yes.  Re-read what I wrote.  To put it another way, "mkfs S1 + resize to 
S2" does not produce precisely the same layout as "mkfs S2".

	Jeff