Connection Pool Exception: Cannot get a connection, pool error Timeout waiting for idle object

I am running a web application in Production that recently crashed after it was under some stress. I would guess 100-300 people were accessing the site at similar times, which I would expect to work fine. The logs around the time of the crash are: ``` org.codehaus.groovy.grails.web.taglib.exceptions.GrailsTagException: Error executing tag <g:render>: Hibernate operation: could not inspect JDBC autocommit mode; uncategorize\ d SQLException for SQL [???]; SQL state [null]; error code [0]; Cannot get a connection, pool error Timeout waiting for idle object; nested exception is org.apache.commons.db\ cp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object at /WEB-INF/grails-app/views/layouts/file.gsp:37 at gsp_file_gsp$_run_closure2.doCall(file_gsp.groovy:43) at gsp_file_gsp$_run_closure2.doCall(file_gsp.groovy) at gsp_file_gsp.run(gsp_file_gsp.groovy:48) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:190) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:291) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:774) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703) at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:896) at java.lang.Thread.run(Thread.java:662) Caused by: org.springframework.jdbc.UncategorizedSQLException: Hibernate operation: could not inspect JDBC autocommit mode; uncategorized SQLException for SQL [???]; SQL stat\ e [null]; error code [0]; Cannot get a connection, pool error Timeout waiting for idle object; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot get a co\ nnection, pool error Timeout waiting for idle object at User.find(User.groovy:68) at User$find.call(Unknown Source) at gsp_pps_file_gsp.run(gsp_file_gsp.groovy:22) ... 9 more Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:114) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) at $Proxy7.getAutoCommit(Unknown Source) ... 12 more Caused by: java.util.NoSuchElementException: Timeout waiting for idle object at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1144) at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:106) ... 14 more ``` I believe this is directly related to some code I added recently to my Grails project that affect the Connection Pool (although I believe this is not a grails specific problem): ``` maxActive = 50 maxIdle = 15 minIdle = 5 initialSize = 15 minEvictableIdleTimeMillis = 180000 timeBetweenEvictionRunsMillis = 180000 maxWait = 10000 validationQuery = "/* ping */" ``` What am I doing wrong? Please help! Thank you.