Re: [HACKERS] logical decoding of two-phase transactions

Ajin Cherian <itsajin@gmail.com>

From: Ajin Cherian <itsajin@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Dilip Kumar <dilipbalaut@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Masahiko Sawada <sawada.mshk@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2020-09-28T07:42:56Z
Lists: pgsql-hackers

Attachments

On Wed, Sep 23, 2020 at 2:39 PM Amit Kapila <amit.kapila16@gmail.com> wrote:

> No problem. I think you can handle the other comments and then we can
> come back to this and you might want to share the exact details of the
> test (may be a narrow down version of the original test) and I or
> someone else might be able to help you with that.
>
> --
> With Regards,
> Amit Kapila.

I have added a new patch for supporting 2 phase commit semantics in
the streaming APIs for the logical decoding plugins. I have added 3
APIs
1. stream_prepare
2. stream_commit_prepared
3. stream_abort_prepared

I have also added the support for the new APIs in test_decoding
plugin. I have not yet added it to pgoutpout.

I have also added a fix for the error I saw while calling
ReorderBufferCleanupTXN as part of FinishPrepared handling. As a
result I have removed the function I added earlier,
ReorderBufferCleanupPreparedTXN.
Please have a look at the new changes and let me know what you think.

I will continue to look at:

1. Remove snapshots on prepare truncate.
2. Bug seen while abort of prepared transaction, the prepared flag is
lost, and not able to make out that it was a previously prepared
transaction.

regards,
Ajin Cherian
Fujitsu Australia

Commits

  1. Add prepare API support for streaming transactions in logical replication.

  2. Doc: minor improvements for logical replication protocol documentation.

  3. Fix test failure in 021_twophase.pl.

  4. Refactor to make common functions in proto.c and worker.c.

  5. Unify PostgresNode's new() and get_new_node() methods

  6. Fix potential buffer overruns in proto.c.

  7. Add support for prepared transactions to built-in logical replication.

  8. Refactor function parse_subscription_options.

  9. Allow enabling two-phase option via replication protocol.

  10. Don't use Asserts to check for violations of replication protocol.

  11. Improve psql tab completion for options of subcriptions and publications

  12. Rearrange logrep worker's snapshot handling some more.

  13. doc: Update information of new messages for logical replication.

  14. ALTER SUBSCRIPTION ... ADD/DROP PUBLICATION

  15. Allow pgoutput to send logical decoding messages.

  16. Refactor function parse_output_parameters.

  17. Avoid repeated decoding of prepared transactions after a restart.

  18. Fix an oversight in ReorderBufferFinishPrepared.

  19. Allow multiple xacts during table sync in logical replication.

  20. Fix replication of in-progress transactions in tablesync worker.

  21. Fix 'skip-empty-xacts' option in test_decoding for streaming mode.

  22. Use Enum for top level logical replication message types.

  23. Add support for streaming to built-in logical replication.

  24. Fix the logical streaming test.

  25. Implement streaming mode in ReorderBuffer.

  26. Extend the logical decoding output plugin API with stream methods.

  27. Store 2PC GID in commit/abort WAL recs for logical decoding