Re: fixing old_snapshot_threshold's time->xid mapping
Anastasia Lubennikova <a.lubennikova@postgrespro.ru>
From: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>
To: Thomas Munro <thomas.munro@gmail.com>,
Michael Paquier <michael@paquier.xyz>
Cc: Robert Haas <robertmhaas@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>,
Andres Freund <andres@anarazel.de>, Kevin Grittner <kgrittn@gmail.com>,
"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2020-11-26T10:03:56Z
Lists: pgsql-hackers
On 06.10.2020 08:32, Thomas Munro wrote: > On Fri, Sep 25, 2020 at 2:00 PM Michael Paquier <michael@paquier.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: http://www.postgrespro.com The Russian Postgres Company
Commits
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Remove the "snapshot too old" feature.
- f691f5b80a85 17.0 landed
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Fix two bugs in MaintainOldSnapshotTimeMapping.
- 55b7e2f4d78d 14.0 landed
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Add new 'old_snapshot' contrib module.
- aecf5ee2bb36 14.0 landed
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Expose oldSnapshotControl definition via new header.
- f5ea92e8d620 14.0 landed