database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-26 12:21:12 +03:00
Code Activity

Remove the unnecessary PrepareWrite in pgoutput.

Browse Source 
This issue exists from the inception of this code (PG-10) but got exposed
by the recent commit ce0fdbfe97 where we are using origins in tablesync
workers. The problem was that we were sometimes sending the prepare_write
('w') message but then the actual message was not being sent and on the
subscriber side, we always expect a message after prepare_write message
which led to this bug.

I refrained from backpatching this because there is no way in the core
code to hit this prior to commit ce0fdbfe97 and we haven't received any
complaints so far.

Reported-by: Erik Rijkers
Author: Amit Kapila and Vignesh C
Tested-by: Erik Rijkers
Discussion: https://postgr.es/m/1295168140.139428.1613133237154@webmailclassic.xs4all.nl
This commit is contained in:
Amit Kapila
2021-02-16 07:26:50 +05:30
parent 8001cb77ee
commit f672df5fdd
2 changed files with 80 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
src/backend/replication/pgoutput/pgoutput.c
View File

@ -342,10 +342,6 @@ pgoutput_begin_txn(LogicalDecodingContext *ctx, ReorderBufferTXN *txn)
{
char *origin;
/* Message boundary */
OutputPluginWrite(ctx, false);
OutputPluginPrepareWrite(ctx, true);
/*----------
* XXX: which behaviour do we want here?
*
@ -357,7 +353,13 @@ pgoutput_begin_txn(LogicalDecodingContext *ctx, ReorderBufferTXN *txn)
*----------
*/
if (replorigin_by_oid(txn->origin_id, true, &origin))
{
/* Message boundary */
OutputPluginWrite(ctx, false);
OutputPluginPrepareWrite(ctx, true);
logicalrep_write_origin(ctx->out, origin, txn->origin_lsn);
}
}
OutputPluginWrite(ctx, true);
@ -780,12 +782,13 @@ pgoutput_stream_start(struct LogicalDecodingContext *ctx,
{
char *origin;
/* Message boundary */
OutputPluginWrite(ctx, false);
OutputPluginPrepareWrite(ctx, true);
if (replorigin_by_oid(txn->origin_id, true, &origin))
{
/* Message boundary */
OutputPluginWrite(ctx, false);
OutputPluginPrepareWrite(ctx, true);
logicalrep_write_origin(ctx->out, origin, InvalidXLogRecPtr);
}
}
OutputPluginWrite(ctx, true);