This environment variable is optional.

On the source platform the Common Work Area (CWA) is shared by all the Programs executing inside a single CICS Region. The size of this CICS zone can vary from 0 to 32765 bytes, 0 indicating that no CWA is defined.

On the target platform, the KIX_CWA_SIZE variable also indicates the size of the CWA, ranging from 0 to 32765 bytes. If this environment variable is not set, the value defaults to 0. A value of zero (either explicit or implicit) indicates that no CWA is defined.