48. WOW Performance

WOW Performance

WOW utilizes the JDBC database servers that are specified in the connection definitions therefore,

typically, performance is nearly all outside of WOW's control.

What happens is:

WOW passes an SQL statement to the server (AS400).

The server (AS400) executes the statement using the best known optimization, as determined by database

code. This includes such factors as file size and database indexes.

After execution, WOW reads the data returned from the server (AS400), generates HTML, and then sends

the HTML to the browser. Thus, nearly all performance is dependent on the database server (AS400).

However, WOW does have facilities to control and enhance performance as shown in the sections that follow.

WOW's Built In High Performance Cache

WOW allows the user to set a caching level for each operation:

The Caching options let you control how WOW stores data so it can be used later. By allowing WOW to

retrieve the data from the cache, a call to the database server can be avoided when the operation is run.

For more details on the caching level, see chapter “Create User Operations”, section “User Operations” in

the WOW Builder’s Guide p.1.

Connection Properties

Each JDBC database driver allows properties to be passed to the database server. You can specify these

properties in the connection definition:

For the IBM AS/400 Remote driver, these can be found in the IBM i Infocenter.

By default, WOW sets the following two AS/400 properties on a new connection:

• • prompt=false - Specifies whether the user is prompted if a user name or password is needed to

    • connect to the server. If a connection cannot be made without prompting the user, and this

    • property is set to "false", then an attempt to connect will fail.

  • trace=false - Specifies whether trace messages are logged. Trace messages are useful for debugging

    • programs that call JDBC. However, there is a performance penalty associated with logging trace

    • messages, so this property should only set to "true" for debugging. Trace messages are logged to

    • System.out.

    • NOTE: Each property begins with a ';'.

You can also affect performance by setting the number of maximum connections allowed:

The default is ten. The maximum number of connections used can have a significant affect on your

performance. This number will vary based on the power of the system.