Re: CLUSTER TODO item

Gavin, please continue working on this feature and continue discussion
the hackers list.

---------------------------------------------------------------------------

Gavin Sherry wrote:
> On Thu, 11 Oct 2001, Tom Lane wrote:
>
> > Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > > Can I get a status on this?
> >
> > It's not gonna happen for 7.2, I think ...
> >
> > regards, tom lane
>
> I'd love it to go out with 7.2 but I've had no time to work on this patch
> lately. The reason I need time is that, after having fiddled a fair bit,
> I've decided that there really needs to be support for the creation of a
> new relfilenode in the storage manager.
>
> The current patch works like this:
>
> Create new heap (heap_create())
> Copy tuples from old heap to new heap via index scan
> Form a new pg_class tuple
> simple_heap_update()
> update catalogue indices
> rebuild existing indices
>
> This causes an overflow in the localbuf.c so I guess this is wrong
> (included in patch on 24/sep) =). I've looked at various combinations of
> this:
>
> memcpy() the old Relation into a new Relation, update smgrunlink() the old
> Relation and heap_storage_create() the new relation. This dies because
> smgrunlink only schedules the drop, where as heap_storage_create() actually
> creates a file on the file system (open() returns with EEXIST).
>
> I've also tried just copying the structure but heap_open() relies on OID
> not relfilenode.
>
> I'm probably going about it the wrong way, but it strikes me that there
> needs to be a way to abstract the relfilenode from OID in the heap access
> code so that one can easily manipulate the heap on disk without having to
> play with OIDs.
>
> I would have included code examples/clearer description but the box I
> don't have access to the box I created the patches on atm =(.
>
> Gavin
>
>

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026