mirror of
https://github.com/MariaDB/server.git
synced 2025-01-16 12:02:42 +01:00
a83c7ab1ea
Problem: ======== If a primary is shutdown during an active semi-sync connection during the period when the primary is awaiting an ACK, the primary hard kills the active communication thread and does not ensure the transaction was received by a replica. This can lead to an inconsistent replication state. Solution: ======== During shutdown, the primary should wait for an ACK or timeout before hard killing a thread which is awaiting a communication. We extend the `SHUTDOWN WAIT FOR SLAVES` logic to identify and ignore any threads waiting for a semi-sync ACK in phase 1. Then, before stopping the ack receiver thread, the shutdown is delayed until all waiting semi-sync connections receive an ACK or time out. The connections are then killed in phase 2. Notes: 1) There remains an unresolved corner case that affects this patch. MDEV-28141: Slave crashes with Packets out of order when connecting to a shutting down master. Specifically, If a slave is connecting to a master which is actively shutting down, the slave can crash with a "Packets out of order" assertion error. To get around this issue in the MTR tests, the primary will wait a small amount of time before phase 1 killing threads to let the replicas safely stop (if applicable). 2) This patch also fixes MDEV-28114: Semi-sync Master ACK Receiver Thread Can Error on COM_QUIT Reviewed By ============ Andrei Elkin <andrei.elkin@mariadb.com> |
||
|---|---|---|
| .. | ||
| client.c | ||
| client_plugin.c | ||
| conf_to_src.c | ||
| errmsg.c | ||
| my_time.c | ||
| my_user.c | ||
| mysql_async.c | ||
| pack.c | ||