3 Replies Latest reply on Dec 3, 2010 7:29 PM by theglauber

    When and why does JBoss open more database connections than the maximum requested?

    theglauber

      I have a data source configured like this:

      <datasources>
        <ha-local-tx-datasource>

      <datasources>
        <ha-local-tx-datasource>
      
      ...
          <min-pool-size>25</min-pool-size>
          <max-pool-size>30</max-pool-size>
      
          <validate-on-match>true</validate-on-match>
          <background-validation>true</background-validation>
          <background-validation-minutes>17</background-validation-minutes>
          <prefill>true</prefill>
          <set-tx-query-timeout>true</set-tx-query-timeout>
          <query-timeout>60</query-timeout>
      
       
        </ha-local-tx-datasource>
      </datasources>
      

       

      In my interpretation, his should mean:

      • start with 25 connections
      • grow to 30 if needed
      • but not more than 30

       

      I have seen in several occasions the number of open connections go higher than 30. Some times i could correlate this with high activity, but not always. I've heard the number of connections went once to over 100 with no apparent provocation.

       

      Is this a known problem or feature? What triggers it?

       

      JBoss version: [4.3.0.GA_CP03 (build: SVNTag=JBPAPP_4_3_0_GA_CP03 date=200810241616)]

       

      Thank you for any help or ideas.

       

      glauber