RE: Is this a problem in GenericXLogFinish()?

Dear hackers,

> Dear Amit, Michael,
>
> Thanks for making the patch!
>
> > Why register wbuf at all if there are no tuples to add and it is not
> > the same as bucketbuf? Also, I think this won't be correct if prevbuf
> > and wrtbuf are the same and also we have no tuples to add to wbuf. I
> > have attached a naive and crude way to achieve it. This needs more
> > work both in terms of trying to find a better way to change the code
> > or ensure this won't break any existing case. I have just run the
> > existing tests. Such a fix certainly required more testing.
>
> I'm verifying the idea (currently it seems OK), but at least there is a coding error -
> wbuf_flags should be uint8 here. PSA the fixed patch.

Here is a new patch which is bit refactored. It did:

* If-conditions in _hash_freeovflpage() were swapped.
* Based on above, an Assert(xlrec.ntups == 0) was added.
* A condition in hash_xlog_squeeze_page() was followed the change as well
* comments were adjusted

Next we should add some test codes. I will continue considering but please post anything
If you have idea.

Best Regards,
Hayato Kuroda
FUJITSU LIMITED