Skip to main content


Set the size of an InterJob Communication buffer.


[config]    ijcbuff=n

n is an integer in the range 512—8192 (bytes). InterSystems recommends you use the default of 512.


ijcbuff is the number of bytes allocated for each InterJob Communication (IJC) buffer. For details, see Interprocess Communication. Also see the parameter ijcnum.

Changing This Parameter

On the Advanced Memory page of the Management Portal (System Administration > Configuration > Additional Settings > Advanced Memory), in the ijcbuff row, select Edit. Enter a number of bytes.

Instead of using the Management Portal, you can change ijcbuff in the Config.configOpens in a new tab class (as described in the class reference) or by editing the CPF in a text editor (as described in Editing the Active CPF).

If you edit this setting, you must restart InterSystems IRIS® data platform to apply the change.

FeedbackOpens in a new tab