Re: [HACKERS] [WIP] Effective storage of duplicates in B-tree index.

Peter Geoghegan <pg@bowt.ie>

From: Peter Geoghegan <pg@bowt.ie>

To: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>

Cc: Heikki Linnakangas <hlinnaka@iki.fi>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Юрий Соколов <funny.falcon@gmail.com>

Date: 2020-02-25T00:54:53Z

Lists: pgsql-hackers

Attachments

v34-0003-Teach-pageinspect-about-nbtree-posting-lists.patch (application/octet-stream) patch v34-0003
v34-0004-DEBUG-Show-index-values-in-pageinspect.patch (application/octet-stream) patch v34-0004
v34-0002-Add-deduplication-to-nbtree.patch (application/octet-stream) patch v34-0002
v34-0001-Add-equalimage-B-Tree-support-functions.patch (application/octet-stream) patch v34-0001

On Thu, Feb 20, 2020 at 12:59 PM Peter Geoghegan <pg@bowt.ie> wrote:
> I wasn't clear about the implication of what I was saying here, which
> is: I will make the NOTICE a DEBUG1 message, and leave everything else
> as-is in the initial committed version.

Attached is v34, which has this change. My plan is to commit something
very close to this on Wednesday morning (barring any objections).

Other changes:

* Now, equalimage functions take a pg_type OID argument, allowing us
to reuse the same generic pg_proc-wise function across many of the
operator classes from the core distribution.

* Rewrote the docs for equalimage functions in the 0001-* patch.

* Lots of copy-editing of the "Implementation" section of the B-Tree
doc chapter, most of which is about deduplication specifically.

-- 
Peter Geoghegan

Commits

Teach pageinspect about nbtree deduplication.
- 93ee38eade1b 13.0 landed
Doc: Fix deduplicate_items index term.
- e537aed61db7 13.0 landed
Revise BTP_HAS_GARBAGE nbtree VACUUM comments.
- 4b25f5d0ba01 13.0 cited
Remove unneeded "pin scan" nbtree VACUUM code.
- 9f83468b3536 13.0 landed
Cleanup code in reloptions.h regarding reloption handling
- 50d22de9325f 13.0 cited
Catch invalid typlens in a couple of places
- 8557a6f10ca6 13.0 cited
Compute XID horizon for page level index vacuum on primary.
- 558a9165e081 12.0 cited
Make heap TID a tiebreaker nbtree index column.
- dd299df8189b 12.0 cited
Avoid pin scan for replay of XLOG_BTREE_VACUUM in all cases
- 3e4b7d87988f 9.6.0 cited
Revert buggy optimization of index scans
- c7111d11b188 9.6.0 cited
Restructure index access method API to hide most of it at the C level.
- 65c5fcd353a8 9.6.0 cited
Reduce pinning and buffer content locking for btree scans.
- 2ed5b87f96d4 9.5.0 cited
Avoid scanning nulls at the beginning of a btree index scan.
- 1a77f8b63d15 9.2.0 cited