Re: Minimal logical decoding on standbys

Jeff Davis <pgsql@j-davis.com>

From: Jeff Davis <pgsql@j-davis.com>
To: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>, Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Ibrar Ahmed <ibrar.ahmad@gmail.com>, Amit Khandekar <amitdkhan.pg@gmail.com>, fabriziomello@gmail.com, tushar <tushar.ahuja@enterprisedb.com>, Rahila Syed <rahila.syed@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2023-04-02T21:25:35Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Reduce the log level in 035_standby_logical_decoding.pl.

  2. 035_standby_logical_decoding: Add missing waits for replication

  3. For cascading replication, wake physical and logical walsenders separately

  4. Handle logical slot conflicts on standby

  5. Support invalidating replication slots due to horizon and wal_level

  6. Prevent use of invalidated logical slot in CreateDecodingContext()

  7. Replace replication slot's invalidated_at LSN with an enum

  8. Pass down table relation into more index relation functions

  9. Assert only valid flag bits are passed to visibilitymap_set()

  10. Remove unused _bt_delitems_delete() argument.

  11. Add xl_btree_delete optimization.

On Fri, 2023-03-31 at 02:44 -0700, Jeff Davis wrote:
> Thank you, done. I think the nearby line was also wrong, returning
> true
> when there was no timeout. I combined the lines and got rid of the
> early return so it can check the list and timeout condition like
> normal. Attached.

On second (third?) thought, I think I was right the first time. It
passes the flag WL_EXIT_ON_PM_DEATH (included in the
ConditionVariableWaitSet), so a WL_POSTMASTER_DEATH event should not be
returned.

Also, I think the early return is correct. The current code in
ConditionVariableTimedSleep() still checks the wait list even if
WaitLatch() returns WL_TIMEOUT (it ignores the return), but I don't see
why it can't early return true. For a socket event in
ConditionVariableEventSleep() I think it should early return false.

Regards,
	Jeff Davis