Re: Undo worker and transaction rollback

On Mon, Nov 5, 2018 at 5:10 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>
> On Thu, Oct 11, 2018 at 11:30 AM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> >
> > Hello, hackers,
> >
> > In previous threads[1], we proposed patches for generating and storing
> > undo records and now for undo-worker and the transaction rollback
> > stuff. The idea is that undo remains relevant as long as the
> > transaction is in progress and needs to be removed once it becomes
> > irrelevant. Specifically, for a committed transaction, it remains
> > relevant until the transaction becomes all-visible; zheap will use
> > this for MVCC purposes. However, for an aborted transaction, it
> > remains relevant until the “undo actions" described by the undo
> > records have been performed. This patch introduces code to discard
> > undo when it is no longer needed and reuse the associated storage.
> > Additionally, this patch adds code to execute undo actions. Let me
> > explain the finer details for each of the cases covered,
>
> Latest rebased patch for undo worker and transaction rollback. This
> patch includes some bug fixes from the main zheap branch and also
> include code for executing undo action using RMGR (RMGR related code
> is merged from Thomas' patch set for "POC: Cleaning up orphaned files
> using undo logs"[1]. This patch can be applied on top of undolog and
> undo-interface patches.
>
> [1] https://www.postgresql.org/message-id/flat/CAEepm=0ULqYgM2aFeOnrx6YrtBg3xUdxALoyCG+XpssKqmezug(at)mail(dot)gmail(dot)com

Updated patch, include defect fix from Kuntal posted on [1].

[1] https://www.postgresql.org/message-id/CAGz5QCKpCG6egFAdazC%2BJgyk7YSE1OBN9h-QpwCkg-NnSWN5AQ%40mail.gmail.com

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