summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlvaro Herrera2019-09-13 19:36:28 +0000
committerAlvaro Herrera2019-09-13 19:36:28 +0000
commite8c7f40a1f8ad2a017ff646f19ef42b07bf4ab51 (patch)
tree9882bd4306d3d4c86cbfebbaabaf292d8af4cac0
parentca08ea52bfbc0e02eb7e866bb05bf166f15c9b75 (diff)
logical decoding: process ASSIGNMENT during snapshot build
Most WAL records are ignored in early SnapBuild snapshot build phases. But it's critical to process some of them, so that later messages have the correct transaction state after the snapshot is completely built; in particular, XLOG_XACT_ASSIGNMENT messages are critical in order for sub-transactions to be correctly assigned to their parent transactions, or at least one assert misbehaves, as reported by Ildar Musin. Diagnosed-by: Masahiko Sawada Author: Masahiko Sawada Discussion: https://postgr.es/m/CAONYFtOv+Er1p3WAuwUsy1zsCFrSYvpHLhapC_fMD-zNaRWxYg@mail.gmail.com
-rw-r--r--src/backend/replication/logical/decode.c13
1 files changed, 8 insertions, 5 deletions
diff --git a/src/backend/replication/logical/decode.c b/src/backend/replication/logical/decode.c
index 45742636999..d1e45d330fa 100644
--- a/src/backend/replication/logical/decode.c
+++ b/src/backend/replication/logical/decode.c
@@ -202,12 +202,15 @@ DecodeXactOp(LogicalDecodingContext *ctx, XLogRecordBuffer *buf)
uint8 info = r->xl_info & ~XLR_INFO_MASK;
/*
- * No point in doing anything yet, data could not be decoded anyway. It's
- * ok not to call ReorderBufferProcessXid() in that case, except in the
- * assignment case there'll not be any later records with the same xid;
- * and in the assignment case we'll not decode those xacts.
+ * If the snapshot isn't yet fully built, we cannot decode anything, so
+ * bail out.
+ *
+ * However, it's critical to process XLOG_XACT_ASSIGNMENT records even
+ * when the snapshot is being built: it is possible to get later records
+ * that require subxids to be properly assigned.
*/
- if (SnapBuildCurrentState(builder) < SNAPBUILD_FULL_SNAPSHOT)
+ if (SnapBuildCurrentState(builder) < SNAPBUILD_FULL_SNAPSHOT &&
+ info != XLOG_XACT_ASSIGNMENT)
return;
switch (info)