MDEV-30418 : Setting wsrep_slave_threads causes thread hang #3205
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Problem was that wsrep was disconnected and new slave threads tried to connect to cluster but failed as we were disconnected state. Allow changing wsrep_slave_threads only when wsrep is enabled and we are connected to a cluster. In other cases report error and issue a warning.
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This looks good to me! I just added one question, mainly for my own curiosity. |
| --connection node_2 | ||
| select @@wsrep_slave_threads; | ||
| SET @cluster_address_orig = @@wsrep_cluster_address; | ||
| SET GLOBAL wsrep_cluster_address=AUTO; |
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I'm not very familiar with wsrep. Why does setting to AUTO put the node into a disconnected state?
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Because AUTO is not correct node address see https://mariadb.com/kb/en/galera-cluster-system-variables/#wsrep_cluster_address, here naturally we intentionally set it incorrectly to get node out of cluster.
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Description
Problem was that wsrep was disconnected and new slave threads tried to connect to cluster but failed as
we were disconnected state.
Allow changing wsrep_slave_threads only when wsrep is enabled and we are connected to a cluster. In other cases report error and issue a warning.
Release Notes
TODO: What should the release notes say about this change?
Include any changed system variables, status variables or behaviour. Optionally list any https://mariadb.com/kb/ pages that need changing.
How can this PR be tested?
TODO: modify the automated test suite to verify that the PR causes MariaDB to behave as intended.
Consult the documentation on "Writing good test cases".
If the changes are not amenable to automated testing, please explain why not and carefully describe how to test manually.
Basing the PR against the correct MariaDB version
PR quality check