Setting the memory limits for Node.js

Node.js applications typically require more memory than those written in compiled languages, in part due to the Node.js applications ability to service many client requests simultaneously. You must ensure that CICS and Node.js have enough storage and memory available to run Node.js applications.

About this task

The storage that is required for a Node.js application is not allocated from CICS-managed storage areas such as the DSA, EDSA, or GDSA. but instead uses storage from the available MVS private areas. It is important to ensure that sufficient non-allocated private area region storage is available in the 24-bit, 31-bit, and 64-bit addressing areas. CICS cannot use its short-on-storage mechanism when private area region storage is running low.

Procedure

  1. Ensure that the z/OS® MEMLIMIT parameter is set to a suitable value.
    This parameter limits the amount of 64-bit storage that the CICS® address space can use.

    Node.js uses 64-bit storage, and you must ensure that MEMLIMIT is set to a large enough value for both this and other use of 64-bit storage in the CICS region.

  2. Ensure that the REGION parameter on the startup job stream is large enough for Node.js to run.
    This parameter limits the amount of 31-bit storage that the CICS address space can use.
  3. Ensure 24-bit storage required for each Node.js application is available.