Re: mysql 8 NDB php connections drop, cant connect

[Martin Sköld]

How can you determine a bottleneck in one of the ndbd, has it high CPU load?
Also, is it configured to use more cores, but you only see it using one?
That can be changed with manual configuration, see
https://dev.mysql.com/doc/refman/8.0/en/mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-threadconfig
If you have AutomaticThreadConfig set then you should use available cores.
Assuming of course you are using ndbmtd
https://dev.mysql.com/doc/refman/8.0/en/mysql-cluster-programs-ndbmtd.html

Another thing, failing to connect to a mysql server usually has nothing to do
with the load of the Ndb Cluster. If the MySQL server is heavily loaded due to
certain queries (joins) that cannot be pushed to the Ndb nodes, then that could be a factor.
You should be able to connect, but have transactions time out due to
heavy load on the cluster. The failing to connect is probably something else.



Edited 2 time(s). Last edit at 10/01/2021 03:12PM by Martin Sköld.