Re: 回复：Re: Cache relation sizes?

Thomas Munro <thomas.munro@gmail.com>

From: Thomas Munro <thomas.munro@gmail.com>

To: David Steele <david@pgmasters.net>

Cc: Amit Kapila <amit.kapila16@gmail.com>, Konstantin Knizhnik <k.knizhnik@postgrespro.ru>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, 陈佳昕(步真) <buzhen.cjx@alibaba-inc.com>

Date: 2021-06-16T06:24:01Z

Lists: pgsql-hackers

Attachments

v5-0001-WIP-Track-relation-sizes-in-shared-memory.patch (text/x-patch) patch v5-0001
v5-0002-WIP-Provide-a-lock-free-fast-path-for-smgrnblocks.patch (text/x-patch) patch v5-0002
v5-0003-update-fifo-to-lru-to-sweep-a-valid-cache.patch (text/x-patch) patch v5-0003

No change yet, just posting a rebase to keep cfbot happy.

One thing I'm wondering about is whether it'd be possible, and if so,
a good idea, to make a kind of tiny reusable cache replacement
algorithm, something modern, that can be used to kill several birds
with one stone (SLRUs, this object pool, ...).  Or if the interlocking
requirements make it too integrated.

Commits

Optimize DropRelFileNodesAllBuffers() for recovery.
- bea449c635c0 14.0 cited
Cache smgrnblocks() results in recovery.
- c5315f4f4484 14.0 landed
Use pg_pread() and pg_pwrite() for data files and WAL.
- c24dcd0cfd94 12.0 cited
Add a check to prevent overwriting valid data if smgrnblocks() gives a
- ffae5cc5a602 8.2.0 cited