Re: Undo worker and transaction rollback

From: Dilip Kumar <dilipbalaut(at)gmail(dot)com>
To: pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Undo worker and transaction rollback
Date: 2018-11-05 12:32:06
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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]

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


Dilip Kumar

Attachment Content-Type Size
undoworker-transaction-rollback-v3.patch application/octet-stream 134.3 KB

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