I too experience that problem. Any query hitting the same tables at the same time will cause a performance lag, sometimes very significant lag. For instance, if 1 user sends a vague search query that will return a significant listing that query will block out another user that sends a prikey search that returns a single record.
These queries should not hinder each other in any way when connecting in dirty_read mode. Please keep me informed if you get any information that helps your performance. Kevin -----Original Message----- From: Jos� R�mulo El�as Contreras [mailto:[EMAIL PROTECTED] Sent: Thursday, February 17, 2005 9:11 AM To: [email protected] Subject: SAPDB performance? Hello: I test the performance of SAPDB in two tomcat servers connecting to the same database. Each tomcat server open 10 sessions with the next parameters: DriverManager.getConnection(databaseUrl + databaseName + "?user=" + databaseUser + "&password=" + databasePassword + "&timeout=0&isolation=" + java.sql.Connection.TRANSACTION_READ_UNCOMMITTED); I open 4 differents browser sessions connected 2 to each tomcat server. If I request the same information in each different browser session at the same time the performance go down. The first session connected to tomcatServer1 takes 9 seconds to execute the query, the second session connected to tomcatServer1 takes 12 seconds to execute the query, the third session connected to tomcatServer2 takes 14 seconds to execute the query and the fourth session connected to tomcatServer2 takes 16 seconds to execute the query aproximately. If I open only one browser session to execute the query, then the query takes only 3 seconds. I measured the time before calling the execute method of the statement, and afterwards: // Before execute statement save time (time1) ResultSet rs = statement.executeQuery( sql ); // After execute statement save time (time2) // differenceTime = time2 - time1 Why does the performance go down? How can I correct it? -- MaxDB Discussion Mailing List For list archives: http://lists.mysql.com/maxdb To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
