Re: fixing old_snapshot_threshold's time->xid mapping

From: Anastasia Lubennikova <a(dot)lubennikova(at)postgrespro(dot)ru>
To: Thomas Munro <thomas(dot)munro(at)gmail(dot)com>, Michael Paquier <michael(at)paquier(dot)xyz>
Cc: Robert Haas <robertmhaas(at)gmail(dot)com>, Dilip Kumar <dilipbalaut(at)gmail(dot)com>, Andres Freund <andres(at)anarazel(dot)de>, Kevin Grittner <kgrittn(at)gmail(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: fixing old_snapshot_threshold's time->xid mapping
Date: 2020-11-26 10:03:56
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: pgsql-hackers

On 06.10.2020 08:32, Thomas Munro wrote:
> On Fri, Sep 25, 2020 at 2:00 PM Michael Paquier <michael(at)paquier(dot)xyz> wrote:
>> On Thu, Sep 24, 2020 at 03:46:14PM -0400, Robert Haas wrote:
>>> Thomas, with respect to your part of this patch set, I wonder if we
>>> can make the functions that you're using to write tests safe enough
>>> that we could add them to contrib/old_snapshot and let users run them
>>> if they want. As you have them, they are hedged around with vague and
>>> scary warnings, but is that really justified? And if so, can it be
>>> fixed? It would be nicer not to end up with two loadable modules here,
>>> and maybe the right sorts of functions could even have some practical
>>> use.
> Yeah, you may be right. I am thinking about that. In the meantime,
> here is a rebase. A quick recap of these remaining patches:
> 0001 replaces the current "magic test mode" that didn't really test
> anything with a new test mode that verifies pruning and STO behaviour.
> 0002 fixes a separate bug that Andres reported: the STO XID map
> suffers from wraparound-itis.
> 0003 adds a simple smoke test for Robert's commit 55b7e2f4. Before
> that fix landed, it failed.
>> I have switched this item as waiting on author in the CF app then, as
>> we are not completely done yet.
> Thanks. For the record, I think there is still one more complaint
> from Andres that remains unaddressed even once these are in the tree:
> there are thought to be some more places that lack
> TestForOldSnapshot() calls.

Status update for a commitfest entry.

This entry is "Waiting on author" and the thread was inactive for a
while.  As far as I see, part of the fixes is already committed. Is
there anything left to work on or this patch set needs review now?

Anastasia Lubennikova
Postgres Professional:
The Russian Postgres Company

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Julien Rouhaud 2020-11-26 10:16:17 Re: [Proposal] Global temporary tables
Previous Message Antonin Houska 2020-11-26 09:47:15 Re: POC: Cleaning up orphaned files using undo logs