Small thread stack configured for mysql container

[iNikem]

MySQL testcontainer has a my.cnf override which, among other things, sets thread_stack = 128K. This leads to the following problem:

Caused by: java.sql.SQLException: Thread stack overrun:  7704 bytes used of a 131072 byte stack, and 128000 bytes needed.  Use 'mysqld --thread_stack=#' to specify a bigger stack.
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3970)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3906)
	at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2524)
	at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2677)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2503)
	at com.mysql.jdbc.StatementImpl.executeInternal(StatementImpl.java:839)
	at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:739)
	at org.flywaydb.core.internal.dbsupport.JdbcTemplate.executeStatement(JdbcTemplate.java:238)
	at org.flywaydb.core.internal.dbsupport.SqlScript.execute(SqlScript.java:114)
	... 53 more

This SO thread can be of help: https://stackoverflow.com/questions/8821575/mysql-error-1436-thread-stack-overrun-with-simple-query .
Providing local my.cnf override with thread_stack = 256K solves the problem.

Why mysql testcontainer needs my.cnf at all? Shouldn't the default configuration of MySQL be good enough?

[iNikem]

Providing withConfigurationOverride with empty my.cnf file removes the problem as well.

[rnorth]

Hi @iNikem
We have a default my.cnf file to reduce the memory footprint of the MySQL container; the original defaults are quite memory hungry and we found that this was causing unreliability in hard to debug ways (see #209 and #243)

I suspect the thread_stack setting could be an overoptimization though, and something we can change.
Thanks for reporting this
Richard