Note, the fix for "MDEV-23328 Server hang due to Galera lock conflict resolution" was null-merged. 10.4 version of the fix is coming up separately
Problem: ======== Auto purge of relaylogs stops when relay-log-file is 'slave-relay-log.999999' and slave_parallel_threads is enabled. Analysis: ========= The problem is that in Relay_log_info::inc_group_relay_log_pos() function, when two log names are compared via strcmp() function, it gives correct result, when log name sequence numbers are of same digits(6 digits), But when the number goes to 7 digits, a 999999 compares greater than 1000000, which is wrong, hence the bug. Fix: ==== Extract the numeric extension part of the file name, convert it into unsigned long and compare. Thanks to David Zhao for the contribution.
* Update wrong zip-code
slave_list was used to provide data for SHOW SLAVE HOSTS and Slaves_connected status variable. Introduced binlog_dump_thread_count which is exposed via Slaves_connected (replaces slave_list.records). Store Slave_info on THD and access it by iterating server_threads (replaces slave_list). Added: THD::slave_info binlog_dump_thread_count show_slave_hosts_callback() Removed: slave_list SLAVE_LIST_CHUNK SLAVE_ERRMSG_SIZE slave_list_key() slave_info_free() init_slave_list() end_slave_list() all_slave_list_mutexes init_all_slave_list_mutexes() key_LOCK_slave_list LOCK_slave_list Moved: SLAVE_INFO -> Slave_info register_slave() -> THD::register_slave() unregister_slave() -> THD::unregister_slave() Also removed redundant end_slave() from close_connections(): it is called again soon afterwards by clean_up(). Pre-requisite for clean MDEV-18450 solution.
As reported in MDEV-11969 "there's no way to ditch knowledge" about some domain that is no longer updated on a server. Besides being of annoyance to clutter output in DBA console stale domains can prevent the slave to connect the master as MDEV-12012 witnesses. What domain is obsolete must be evaluated by the user (DBA) according to whether the domain info is still relevant and will the domain ever receive any update. This patch introduces a method to discard obsolete gtid domains from the server binlog state. The removal requires no event group from such domain present in existing binlog files though. If there are any the containing logs must be first PURGEd in order for FLUSH BINARY LOGS DELETE_DOMAIN_ID=(list-of-domains) succeed. Otherwise the command returns an error. The list of obsolete domains can be computed through intersecting two sets - the earliest (first) binlog's Gtid_list and the current value of @@global.gtid_binlog_state - and extracting the domain id components from the intersection list items. The new DELETE_DOMAIN_ID featured FLUSH continues to rotate binlog omitting the deleted domains from the active binlog file's Gtid_list. Notice though when the command is ineffective - that none of requested to delete domain exists in the binlog state - rotation does not occur. Obsolete domain deletion is not harmful for connected slaves as long as master side binlog files *purge* is synchronized with FLUSH-DELETE_DOMAIN_ID. The slaves must have the last event from purged files processed as usual, in order not to bump later into requesting a gtid from a file which was already gone. While the command is not replicated (as ordinary FLUSH BINLOG LOGS is) slaves, even though having extra domains, won't suffer from reconnection errors thanks to master-slave gtid connection protocol allowing the master to be ignorant about a gtid domain. Should at failover such slave to be promoted into master role it may run the ex-master's FLUSH BINARY LOGS DELETE_DOMAIN_ID=(list-of-domains) to clean its own binlog state. NOTES. suite/perfschema/r/start_server_low_digest.result is re-recorded as consequence of internal parser codes changes.