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Allow InterSystems IRIS® data platform to use the Nagle algorithm for Telnet.


[Miscellaneous]    UseNagleAlgorithm=n

n is either 1 (true) or 0 (false). The default value is 0.


When UseNagleAlgorithm is enabled (n = 1), InterSystems IRIS uses the Nagle algorithm for Telnet.

The Nagle algorithm makes Telnet more efficient. It reduces the number of IP packets sent over the network by consolidating messages that are sent within a small time interval into a single IP packet. When the Nagle algorithm is enabled, the operating system waits some interval before actually committing the data from a send command, in the hopes that the application calls send again with more data that can be consolidated with the first. For more details see RFC 896.

Changing This Parameter

On the Compatibility page of the Management Portal (System Administration > Configuration > Additional Settings > Compatibility), in the UseNagleAlgorithm row, click Edit. Select UseNagleAlgorithm to enable this setting.

Instead of using the Management Portal, you can change UseNagleAlgorithm in the Config.Miscellanous class (as described in the class reference) or by editing the CPF in a text editor (as described in the Editing the Active CPF section of the “Introduction to the Configuration Parameter File” chapter in this book).