Pre-allocating Virtual Terminal Servers

When new virtual terminal sessions (non-telnet) are established, MPE creates a Virtual Terminal Server Process known as a VTSERVER to handle the network communication traffic for the session. This additional overhead can increase the wait time the user sees in obtaining the initial logon prompt, often leading to the perception of a performance problem. You can eliminate this overhead by pre-allocating the vtservers ahead of time when the network is first started. Ordinarily, you start the network services with the command :NSCONTROL START.

To initially designate the servers you first must to know how many you need. You can check this with the command :NSCONTROL STATUS=SERVERS and look at the count in the Active column. If a peak time of day includes 370 active VTSERVERS you might want to allot 400. The command :NSCONTROL START;SERVER=VTSERVER,400,600 will immediately create 400 VTSERVERS with a maximum of 600.

The default maximum is 300 so you must specify a number larger than initially allocated. If you are initially allocating less than 300 then you need not specify the second parameter. Be forewarned that this may take quite some time to complete, as it will create 400 new processes on the system before returning control back to the session or job issuing the command, but this start-up event will pay dividends later as the processes will not have to be created each time your users connect nor will they be killed when the users disconnect.