Fix logical decoding sendtime update
Hi Hackers,
it turns out, that the code in WalSndWriteData is setting the timestamp of
the replication message just *after* it has been sent out to the client,
thus the sendtime field always reads as zero.
Attached is a trivial patch to fix this. The physical replication path
already does the correct thing apparently.
Cheers!
--
Alex
Attachments:
logical-decoding-sendtime-fix.difftext/plain; charset=US-ASCII; name=logical-decoding-sendtime-fix.diffDownload
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
new file mode 100644
index eb1b89b..c9444ca
*** a/src/backend/replication/walsender.c
--- b/src/backend/replication/walsender.c
*************** static void
*** 1048,1056 ****
WalSndWriteData(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid,
bool last_write)
{
- /* output previously gathered data in a CopyData packet */
- pq_putmessage_noblock('d', ctx->out->data, ctx->out->len);
-
/*
* Fill the send timestamp last, so that it is taken as late as possible.
* This is somewhat ugly, but the protocol's set as it's already used for
--- 1048,1053 ----
*************** WalSndWriteData(LogicalDecodingContext *
*** 1061,1066 ****
--- 1058,1066 ----
memcpy(&ctx->out->data[1 + sizeof(int64) + sizeof(int64)],
tmpbuf.data, sizeof(int64));
+ /* output previously gathered data in a CopyData packet */
+ pq_putmessage_noblock('d', ctx->out->data, ctx->out->len);
+
/* fast path */
/* Try to flush pending output to the client */
if (pq_flush_if_writable() != 0)
On 2015-06-10 17:57:42 +0200, Shulgin, Oleksandr wrote:
it turns out, that the code in WalSndWriteData is setting the timestamp of
the replication message just *after* it has been sent out to the client,
thus the sendtime field always reads as zero.
Ugh, what a stupid bug. Thanks!
Andres
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