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Allocate shared memory for caching routine buffers.


[config]    routines=n
[config]    routines=n1, n2, n3, n4, n5, n6


routines specifies the amount of memory to allocate for caching routine buffers. You can do this in two ways — either specifying a single value or specifying values for all six buffer sizes.

You can specify only a single value, n, for the total size, in megabytes, of shared memory that InterSystems IRIS® data platform allocates for routine buffers. InterSystems IRIS divides this memory into the various buffer sizes for optimum performance. While the default value is 0, InterSystems IRIS always allocates a minimum of 35 MB. The maximum value for n is 1023.

You can instead specify the amount of memory to allocate for each routine buffer size. If you use this format, you must specify all six values; if fewer than six are given, InterSystems IRIS reverts to the first format, using n1 as the value for n. The six values represent the following:

  • n1 is the number of MB allocated for 2 KB routine buffers.

  • n2 is the number of MB allocated for 4 KB routine buffers.

  • n3 is the number of MB allocated for 8 KB routine buffers.

  • n4 is the number of MB allocated for 16 KB routine buffers.

  • n5 is the number of MB allocated for 32 KB routine buffers.

  • n6 is the number of MB allocated for 64 KB routine buffers.

The total number of buffers cannot exceed 33,554,432. If the total number of buffers exceeds this number, it is reduced to the maximum. It is possible to have 0 buffers of a certain kind, but the next minimum value is 430 (if a smaller number of buffers is specified, the system adjusts up to 430).

For more information, see Calculating Memory Requirements and Allocation in the “Vertically Scaling InterSystems IRIS” chapter of the Scalability Guide and Allocating Memory to the Routine and Database Caches in the “Configuring InterSystems IRIS” chapter of the System Administration Guide.



Allocate 256 MB for routine buffers, divided into various sizes by an internal formula.


Allocate 1056 MB for routine buffers, divided into 53,760 total buffers.


To allocate a minimum number of buffers, enter a single value of 0.

Changing This Parameter

On the Memory and Startup page of the Management Portal (System Administration > Configuration > System Configuration > Memory and Startup), select the option to Configure Memory Settings Manually. In the Memory Allocated for Routine Cache (MB) field, enter a number of megabytes.

Instead of using the Management Portal, you can change routines in the Config.config 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).