Messages in this thread | | | Date | Fri, 09 Jun 2006 13:07:37 -0400 | From | Jeff Garzik <> | Subject | Re: [RFC 0/13] extents and 48bit ext3 |
| |
Andrew Morton wrote: > On Fri, 09 Jun 2006 11:40:03 -0400 > Jeff Garzik <jeff@garzik.org> wrote: > >> Users are now forced to remember that, if they write to their filesystem >> after using either $mmver or $korgver kernels, they are locked out of >> using older kernels. > > The same happens if we create ext4 - earlier kernels don't support that, > either. > > I suppose we could call it ext4, although that wouldn't make much > difference operationally. The developers would probably choose to generate > ext4 from the same codebase as ext3 for maintainability reasons, rather > than choosing to copy-n-modify. We'd need to see the patches to be able to > finally make that judgement.
I would propose the obvious... 'cp -a ext3 ext4', apply the extent and 48bit patches, and then do the obvious search-n-replace.
I guarantee that developer momentum would take over from there. Rather than fundamentally change ext3, let's let it stabilize.
>> And as features continue to be added in this manner, this problem gets >> _exponentially_ worse. > > "continue to be added"? afaik this is the first time this has happened, > and there's no plan to do it again.
ext3 developers are _fundamentally changing_ the block allocation structure [in a good way]. If they can get away with it once, they will continue to modify ext3, adding btrees and other new gadgets. That's just human nature. For example, htree was a minor disaster, deployment-wise, on the distro vendor side.
I think extents and 48bit are so fundamental that it's silly to attempt to minimize the impact from the user's perspective, and moreover, I think Linux benefits more if ext3 is _not_ kept on life support this way.
We need to draw a line in the sand. If we don't, no one ever will.
Jeff
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |