Re: [HACKERS] logical decoding of two-phase transactions
Amit Kapila <amit.kapila16@gmail.com>
Attachments
- change_two_phase_desc_2.patch (application/octet-stream) patch
On Wed, Mar 17, 2021 at 11:27 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> 5. I have modified the comments atop worker.c to explain the design
> and some of the problems clearly. See attached. If you are fine with
> this, please include it in the next version of the patch.
>
I have further expanded these comments to explain the handling of
prepared transactions for multiple subscriptions on the same server
especially when the same prepared transaction operates on tables for
those subscriptions. See attached, this applies atop the patch sent by
me in the last email. I am not sure but I think it might be better to
add something on those lines in user-facing docs. What do you think?
Another comment:
+ ereport(LOG,
+ (errmsg("logical replication apply worker for subscription \"%s\" 2PC is %s.",
+ MySubscription->name,
+ MySubscription->twophase == LOGICALREP_TWOPHASE_STATE_DISABLED ? "DISABLED" :
+ MySubscription->twophase == LOGICALREP_TWOPHASE_STATE_PENDING ? "PENDING" :
+ MySubscription->twophase == LOGICALREP_TWOPHASE_STATE_ENABLED ? "ENABLED" :
+ "?")));
I don't think this is required in LOGs, maybe at some DEBUG level,
because users can check this in pg_subscription. If we keep this
message, there will be two consecutive messages like below in logs for
subscriptions that have two_pc option enabled which looks a bit odd.
LOG: logical replication apply worker for subscription "mysub" has started
LOG: logical replication apply worker for subscription "mysub" 2PC is ENABLED.
--
With Regards,
Amit Kapila.
Commits
-
Add prepare API support for streaming transactions in logical replication.
- 63cf61cdeb7b 15.0 landed
-
Doc: minor improvements for logical replication protocol documentation.
- a5cb4f9829fb 15.0 cited
-
Fix test failure in 021_twophase.pl.
- eaf5321c3524 15.0 landed
-
Refactor to make common functions in proto.c and worker.c.
- 91f9861242cd 15.0 landed
-
Unify PostgresNode's new() and get_new_node() methods
- 201a76183e20 15.0 cited
-
Fix potential buffer overruns in proto.c.
- 01c3adcdd85f 15.0 landed
-
Add support for prepared transactions to built-in logical replication.
- a8fd13cab0ba 15.0 cited
-
Refactor function parse_subscription_options.
- 8aafb0261675 15.0 cited
-
Allow enabling two-phase option via replication protocol.
- cda03cfed6b8 15.0 cited
-
Don't use Asserts to check for violations of replication protocol.
- fe6a20ce54cb 14.0 cited
-
Improve psql tab completion for options of subcriptions and publications
- d08237b5b494 14.0 cited
-
Rearrange logrep worker's snapshot handling some more.
- 3a09d75b4f6c 14.0 cited
-
doc: Update information of new messages for logical replication.
- 15c1a9d9cb76 14.0 cited
-
ALTER SUBSCRIPTION ... ADD/DROP PUBLICATION
- 82ed7748b710 14.0 cited
-
Allow pgoutput to send logical decoding messages.
- ac4645c0157f 14.0 cited
-
Refactor function parse_output_parameters.
- 531737ddad21 14.0 cited
-
Avoid repeated decoding of prepared transactions after a restart.
- 8bdb1332eb51 14.0 cited
-
Fix an oversight in ReorderBufferFinishPrepared.
- ade89ba5f408 14.0 landed
-
Allow multiple xacts during table sync in logical replication.
- ce0fdbfe9722 14.0 cited
-
Fix replication of in-progress transactions in tablesync worker.
- 0926e96c4934 14.0 cited
-
Fix 'skip-empty-xacts' option in test_decoding for streaming mode.
- 9653f24ad830 14.0 cited
-
Use Enum for top level logical replication message types.
- 644f0d7cc9c2 14.0 cited
-
Add support for streaming to built-in logical replication.
- 464824323e57 14.0 cited
-
Fix the logical streaming test.
- 82a0ba7707e0 14.0 cited
-
Implement streaming mode in ReorderBuffer.
- 7259736a6e5b 14.0 cited
-
Extend the logical decoding output plugin API with stream methods.
- 45fdc9738b36 14.0 cited
-
Store 2PC GID in commit/abort WAL recs for logical decoding
- 1eb6d6527aae 11.0 cited