Db connections number

[alper]

Hi,
I use Activiti Enginein my webapp deployed on JBoss.
I don't use jdbc directly, but JNDI datasource:

processEngine = ProcessEngineConfiguration
            .createStandaloneInMemProcessEngineConfiguration()
            .setDatabaseSchemaUpdate(
                  ProcessEngineConfiguration.DB_SCHEMA_UPDATE_TRUE)
            .setDataSourceJndiName("java:jboss/datasources/ActivitiDS")
‍‍‍‍‍‍‍

I enabled pooling in JBoss by adding into the standalone.xml:

                    <pool>
                        <min-pool-size>50</min-pool-size>
                        <max-pool-size>200</max-pool-size>
                        <prefill>true</prefill>
                    </pool>
‍‍‍‍‍‍‍

But anyway when I concurrently start 100 workflows in separate threads by doing:

runtimeService = processEngine.getRuntimeService();
               ProcessInstance startProcessInstanceByKey = runtimeService
                     .startProcessInstanceByKey("emptyParent", request);
‍‍‍‍‍

I am getting freezed threads and exception at the end:

Error updating database.  Cause: org.h2.jdbc.JdbcSQLException: Timeout trying to lock table "ACT_HI_PROCINST";.

How to cure that?

[alper]

It works without exception for 50 concurrent threads, but for 100 threads 4 of them freeze with this exception.

[alper]

Ok, I increased pool size in the JBoss and everything works well