Re: Removing more vacuumlazy.c special cases, relfrozenxid optimizations

Peter Geoghegan <pg@bowt.ie>

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From: Peter Geoghegan <pg@bowt.ie>

To: Masahiko Sawada <sawada.mshk@gmail.com>

Cc: Andres Freund <andres@anarazel.de>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>

Date: 2022-01-06T19:23:57Z

Lists: pgsql-hackers

Attachments

v5-0002-Improve-log_autovacuum_min_duration-output.patch (application/x-patch) patch v5-0002
v5-0004-Loosen-coupling-between-relfrozenxid-and-tuple-fr.patch (application/x-patch) patch v5-0004
v5-0005-Freeze-tuples-early-to-advance-relfrozenxid.patch (application/x-patch) patch v5-0005
v5-0003-Simplify-vacuum_set_xid_limits-signature.patch (application/x-patch) patch v5-0003
v5-0001-Simplify-lazy_scan_heap-s-handling-of-scanned-pag.patch (application/x-patch) patch v5-0001

On Mon, Dec 20, 2021 at 9:35 PM Peter Geoghegan <pg@bowt.ie> wrote:
> > Given the opportunistic freezing, that's true but I'm concerned
> > whether opportunistic freezing always works well on all tables since
> > freezing tuples is not 0 cost.
>
> That is the big question for this patch.

Attached is a mechanical rebase of the patch series. This new version
just fixes bitrot, caused by Masahiko's recent lazyvacuum.c
refactoring work. In other words, this revision has no significant
changes compared to the v4 that I posted back in late December -- just
want to keep CFTester green.

I still have plenty of work to do here. Especially with the final
patch (the v5-0005-* "freeze early" patch), which is generally more
speculative than the other patches. I'm playing catch-up now, since I
just returned from vacation.

--
Peter Geoghegan

Commits

Have VACUUM warn on relfrozenxid "in the future".
- e83ebfe6d767 15.0 landed
vacuumlazy.c: Further consolidate resource allocation.
- c42a6fc41dc2 15.0 landed
Generalize how VACUUM skips all-frozen pages.
- f3c15cbe5065 15.0 landed
Set relfrozenxid to oldest extant XID seen by VACUUM.
- 0b018fabaaba 15.0 landed
Doc: Add relfrozenxid Tip to XID wraparound section.
- 05023a237c05 15.0 landed
vacuumlazy.c: document vistest and OldestXmin.
- 73f6ec3d3c8d 15.0 cited
Increase hash_mem_multiplier default to 2.0.
- 8f388f6f554b 15.0 cited
Consolidate VACUUM xid cutoff logic.
- efa4a9462a07 15.0 landed
Add VACUUM instrumentation for scanned pages, relfrozenxid.
- 872770fd6ccf 15.0 landed
Simplify lazy_scan_heap's handling of scanned pages.
- 44fa84881fff 15.0 landed
Try to stabilize reloptions test, again.
- b700f96cffd9 15.0 cited
Unify VACUUM VERBOSE and autovacuum logging.
- 49c9d9fcfa9a 15.0 cited
Fix possible HOT corruption when RECENTLY_DEAD changes to DEAD while pruning.
- 18b87b201f73 15.0 cited
pg_resetxlog: add option to set oldest xid & use by pg_upgrade
- 74cf7d46a91d 15.0 cited
Teach VACUUM to bypass unnecessary index vacuuming.
- 5100010ee4d5 14.0 cited
Centralize horizon determination for temp tables, fixing bug due to skew.
- 94bc27b57680 14.0 cited
pg_surgery: Try to stabilize regression tests.
- 0811f766fd74 14.0 cited
Add "split after new tuple" nbtree optimization.
- f21668f328c8 12.0 cited
Fix bugs in vacuum of shared rels, by keeping their relcache entries current.
- a54e1f158779 11.0 cited
Avoid useless truncation attempts during VACUUM.
- e842908233bb 9.6.0 cited
Only skip pages marked as clean in the visibility map, if the last 32
- bf136cf6e376 8.4.0 cited
Fix recently-understood problems with handling of XID freezing, particularly
- 48188e1621bb 8.2.0 cited