Collected from the PG bugs email list.
|OS||x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.3 2|
|Reported by||Nitesh Yadav|
Body of first available message related to this bug follows.
The following bug has been logged on the website: Bug reference: 15744 Logged by: Nitesh Yadav Email address: (redacted) PostgreSQL version: 9.6.3 Operating system: x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.3 2 Description: Hi, Postgres Server setup: Postgres server is running as AWS rds instance. Server Version is PostgreSQL 9.6.3 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.3 20140911 (Red Hat 4.8.3-9), 64-bit With the following parameters group rds.logical_replication is set to 1.Which internally set the following flags: wal_level, max_wal_senders, max_replication_slots, max_connections. We are using test_decoding module for retrieving/read the WAL data through the logical decoding mechanism. Application setup: Periodically we run the peek command to retrieve the data from the slot: eg SELECT * FROM pg_logical_slot_peek_changes('pgldpublic_cdc_slot', NULL, NULL, 'include-timestamp', 'on') LIMIT 200000 OFFSET 0; From the above query result, we use location of last transaction to remove the data from the slot: eg SELECT location, xid FROM pg_logical_slot_get_changes('pgldpublic_cdc_slot', 'B92/C7394678', NULL, 'include-timestamp', 'on') LIMIT 1; We runs Step 1 & 2 in the loop for reading data in the chunk of 200K records at a time in a given process. Behavior reported (Bug) We have a replication slot running for successfully but recently we encountered following error: error: got sequence entry 2 for toast chunk 30954054 instead of seq 0 at Connection.parseE (/var/task/node_modules/datacoral-utils/node_modules/pg/lib/connection.js:555:11) at Connection.parseMessage (/var/task/node_modules/datacoral-utils/node_modules/pg/lib/connection.js:380:19) at TLSSocket.<anonymous> (/var/task/node_modules/datacoral-utils/node_modules/pg/lib/connection.js:120:22) at emitOne (events.js:116:13) at TLSSocket.emit (events.js:211:7) at addChunk (_stream_readable.js:263:12) at readableAddChunk (_stream_readable.js:250:11) at TLSSocket.Readable.push (_stream_readable.js:208:10) at TLSWrap.onread (net.js:607:20) Temporary resolution After running the query 2-3 times, the error went away. But this causes the whole process to shut down. Is there any permanent resolution for the issue or is it resolved in the higher version of postgres? Regards, Nitesh
|2019-04-09 20:09:19+00||PG Bug reporting form||BUG #15744: Replication slot peak query throwing error for wrong sequence entry for toast chunk|
|2019-04-10 08:28:55+00||Peter Eisentraut||Re: BUG #15744: Replication slot peak query throwing error for wrong sequence entry for toast chunk|
|2019-04-10 15:45:28+00||Andres Freund||Re: BUG #15744: Replication slot peak query throwing error for wrong sequence entry for toast chunk|