Sets the number of messages waiting to be sent on a particular network connection at which the high water mark event will occur. When the high water mark is reached, a hardware alarm will be raised. If this occurs on a connection made to the IO Server, the IO Server will suspend value updates being sent to subscriptions until the low water mark has been reached.
If this hardware alarm occurs irregularly (e.g.if there is a spike of activity in a large system) it may indicate that the value of this parameter needs to be increased for this system.
If this hardware alarm occurs regularly, it may indicate there is a problem with the network or with the performance of the server from which the connection has been made. It can also indicate that more value changes are occurring then the system can deal with. The deadbands of some of the variable tags may need to be increased to reduce the number of value changes in the system, or the sample period of the trends or alarm scan time may need to be increased to reduce the number of polls made to the IODevices.
Note: If this parameter is set to a value less than or equal to [LAN]LowWaterMark both of these parameters will be ignored and the system will operate at the default values.
1 to 2147483647
Default Value: 80000