Horton

Re: Skipping logical replication transactions on subscriber side

Masahiko Sawada <sawada.mshk@gmail.com>

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From: Masahiko Sawada <sawada.mshk@gmail.com>
To: Greg Nancarrow <gregn4422@gmail.com>
Cc: "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>, Amit Kapila <amit.kapila16@gmail.com>, "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Alexey Lesovsky <lesovsky@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2021-08-11T05:52:03Z
Lists: pgsql-hackers 
On Tue, Aug 10, 2021 at 10:27 PM Greg Nancarrow <gregn4422@gmail.com> wrote:
>
> On Tue, Aug 10, 2021 at 3:07 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> >
> > I've attached the latest patches that incorporated all comments I got
> > so far. Please review them.
> >
>
> Some initial review comments on the v6-0001 patch:

Thanks for reviewing the patch!

>
>
> src/backend/replication/logical/proto.c:
> (1)
>
> + TimestampTz committs;
>
> I think it looks better to name "committs" as "commit_ts", and also is
> more consistent with naming for other member "remote_xid".

Fixed.

>
> src/backend/replication/logical/worker.c:
> (2)
> To be consistent with all other function headers, should start
> sentence with capital: "get" -> "Get"
>
> + * get string representing LogicalRepMsgType.

Fixed

>
> (3) It looks a bit cumbersome and repetitive to set/update the members
> of apply_error_callback_arg in numerous places.
>
> I suggest making the "set_apply_error_context..." and
> "reset_apply_error_context..." functions as "static inline void"
> functions (moving them to the top part of the source file, and
> removing the existing function declarations for these).
>
> Also, can add something similar to below:
>
> static inline void
> set_apply_error_callback_xid(TransactionId xid)
> {
>    apply_error_callback_arg.remote_xid = xid;
> }
>
> static inline void
> set_apply_error_callback_xid_info(TransactionId xid, TimestampTz commit_ts)
> {
>    apply_error_callback_arg.remote_xid = xid;
>    apply_error_callback_arg.commit_ts = commit_ts;
> }
>
> so that instances of, for example:
>
>    apply_error_callback_arg.remote_xid = prepare_data.xid;
>    apply_error_callback_arg.committs = prepare_data.commit_time;
>
> can be:
>
>    set_apply_error_callback_tx_info(prepare_data.xid, prepare_data.commit_time);

Okay. I've added set_apply_error_callback_xact() function to set
transaction information to apply error callback. Also, I inlined those
helper functions since we call them every change.

>
> (4) The apply_error_callback() function is missing a function header/comment.

Added.

The fixes for the above comments are incorporated in the v7 patch I
just submitted[1].

Regards,

[1] https://www.postgresql.org/message-id/CAD21AoALAq_0q_Zz2K0tO%3DkuUj8aBrDdMJXbey1P6t4w8snpQQ%40mail.gmail.com

-- 
Masahiko Sawada
EDB:  https://www.enterprisedb.com/

Commits

  1. Test ALIGNOF_DOUBLE==4 compatibility under ALIGNOF_DOUBLE==8.

  2. Reorder subskiplsn in pg_subscription to avoid alignment issues.

  3. Add ALTER SUBSCRIPTION ... SKIP.

  4. Optionally disable subscriptions on error.

  5. Update docs of logical replication for commit 8d74fc96db.

  6. Respect permissions within logical replication.

  7. Fix regression test failure caused by commit 8d74fc96db.

  8. Add a view to show the stats of subscription workers.

  9. Add logical change details to logical replication worker errcontext.

  10. Rename LOGICAL_REP_MSG_STREAM_END to LOGICAL_REP_MSG_STREAM_STOP.

  11. Fix typo in protocol.sgml.

  12. Remove unused argument in apply_handle_commit_internal().

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

  14. Reorder pg_sequence columns to avoid alignment issue