Flaky test TestJdbcConnectorTest.testDropColumn

[findepi]

java.lang.RuntimeException: Timeout trying to lock table "SYS"; SQL statement:
ALTER TABLE "TEST-1564957290654751097"."TPCH"."TEST_DROP_COLUMN_MJYG7" DROP COLUMN Y [50200-200]

	at io.trino.testing.AbstractTestingTrinoClient.execute(AbstractTestingTrinoClient.java:120)
	at io.trino.testing.DistributedQueryRunner.execute(DistributedQueryRunner.java:491)
	at io.trino.testing.QueryAssertions.assertUpdate(QueryAssertions.java:71)
	at io.trino.testing.AbstractTestQueryFramework.assertUpdate(AbstractTestQueryFramework.java:215)
	at io.trino.testing.AbstractTestQueryFramework.assertUpdate(AbstractTestQueryFramework.java:210)
	at io.trino.testing.AbstractTestDistributedQueries.testDropColumn(AbstractTestDistributedQueries.java:491)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:104)
	at org.testng.internal.Invoker.invokeMethod(Invoker.java:645)
	at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:851)
	at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1177)
	at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:129)
	at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:112)
	at org.testng.internal.thread.ThreadUtil$2.call(ThreadUtil.java:64)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: io.trino.spi.TrinoException: Timeout trying to lock table "SYS"; SQL statement:
ALTER TABLE "TEST-1564957290654751097"."TPCH"."TEST_DROP_COLUMN_MJYG7" DROP COLUMN Y [50200-200]
	at io.trino.plugin.jdbc.BaseJdbcClient.execute(BaseJdbcClient.java:976)
	at io.trino.plugin.jdbc.BaseJdbcClient.execute(BaseJdbcClient.java:962)
	at io.trino.plugin.jdbc.BaseJdbcClient.dropColumn(BaseJdbcClient.java:769)
	at io.trino.plugin.jdbc.ForwardingJdbcClient.dropColumn(ForwardingJdbcClient.java:274)
	at io.trino.plugin.jdbc.jmx.StatisticsAwareJdbcClient.lambda$dropColumn$17(StatisticsAwareJdbcClient.java:206)
	at io.trino.plugin.jdbc.jmx.JdbcApiStats.wrap(JdbcApiStats.java:47)
	at io.trino.plugin.jdbc.jmx.StatisticsAwareJdbcClient.dropColumn(StatisticsAwareJdbcClient.java:206)
	at io.trino.plugin.jdbc.CachingJdbcClient.dropColumn(CachingJdbcClient.java:371)
	at io.trino.plugin.jdbc.CachingJdbcClient.dropColumn(CachingJdbcClient.java:371)
	at io.trino.plugin.jdbc.JdbcMetadata.dropColumn(JdbcMetadata.java:650)
	at io.trino.metadata.MetadataManager.dropColumn(MetadataManager.java:730)
	at io.trino.execution.DropColumnTask.execute(DropColumnTask.java:91)
	at io.trino.execution.DropColumnTask.execute(DropColumnTask.java:39)
	at io.trino.execution.DataDefinitionExecution.start(DataDefinitionExecution.java:170)
	at io.trino.execution.SqlQueryManager.createQuery(SqlQueryManager.java:237)
	at io.trino.dispatcher.LocalDispatchQuery.lambda$startExecution$7(LocalDispatchQuery.java:143)
	at io.trino.$gen.Trino_testversion____20210308_100114_3.run(Unknown Source)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)
	Suppressed: java.lang.RuntimeException: Query: ALTER TABLE "TEST-1564957290654751097"."TPCH"."TEST_DROP_COLUMN_MJYG7" DROP COLUMN Y
		at io.trino.plugin.jdbc.BaseJdbcClient.execute(BaseJdbcClient.java:977)
		... 19 more
Caused by: org.h2.jdbc.JdbcSQLTimeoutException: Timeout trying to lock table "SYS"; SQL statement:
ALTER TABLE "TEST-1564957290654751097"."TPCH"."TEST_DROP_COLUMN_MJYG7" DROP COLUMN Y [50200-200]
	at org.h2.message.DbException.getJdbcSQLException(DbException.java:511)
	at org.h2.message.DbException.getJdbcSQLException(DbException.java:429)
	at org.h2.message.DbException.get(DbException.java:205)
	at org.h2.message.DbException.get(DbException.java:181)
	at org.h2.mvstore.db.MVTable.doLock1(MVTable.java:207)
	at org.h2.mvstore.db.MVTable.lock(MVTable.java:166)
	at org.h2.engine.Database.lockMeta(Database.java:1000)
	at org.h2.schema.Schema.createTable(Schema.java:682)
	at org.h2.command.ddl.AlterTableAlterColumn.cloneTableStructure(AlterTableAlterColumn.java:414)
	at org.h2.command.ddl.AlterTableAlterColumn.copyData(AlterTableAlterColumn.java:301)
	at org.h2.command.ddl.AlterTableAlterColumn.copyData(AlterTableAlterColumn.java:289)
	at org.h2.command.ddl.AlterTableAlterColumn.update(AlterTableAlterColumn.java:218)
	at org.h2.command.CommandContainer.update(CommandContainer.java:198)
	at org.h2.command.Command.executeUpdate(Command.java:251)
	at org.h2.jdbc.JdbcStatement.executeInternal(JdbcStatement.java:228)
	at org.h2.jdbc.JdbcStatement.execute(JdbcStatement.java:201)
	at io.trino.plugin.jdbc.BaseJdbcClient.execute(BaseJdbcClient.java:973)
	... 19 more

This can be reproduced in locally, with @Test(invocationCount = 200, threadPoolSize = 4), but happened on CI too.
https://github.com/trinodb/trino/runs/2047948730