Re: POC: Cleaning up orphaned files using undo logs

On Mon, May 6, 2019 at 5:43 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> Just for tracking, open comments which still needs to be worked on.
>
> 1.  Avoid special case in UndoRecordIsValid.
> > Can we instead eliminate the special case?  It seems like the if
> > (log->oldest_data == InvalidUndoRecPtr) case will be taken very
> > rarely, so if it's buggy, we might not notice.

I have worked on this comments and added changes in the latest patch.
>
> 2. While updating the previous transaction header instead of unpacking
> complete header and writing it back, we can just unpack main header
> and calculate the offset of uur_next and then update it directly.

For this as you suggested I am not changing, updated the comments.
>
> 3. unifying uur_xid and uur_xidepoch into uur_fxid.
Still open.

I have also added the README.

Patches can be applied on top of undo branch [1] commit:
(cb777466d008e656f03771cf16ec7ef9d6f2778b)

[1] https://github.com/EnterpriseDB/zheap/tree/undo

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com