RLSTOLSR

The RLSTOLSR system initialization parameter specifies whether CICS® is to include files that are to be opened in RLS mode when calculating the number of buffers, strings, and other resources for an LSR pool.

RLSTOLSR={NO|YES}
CICS performs this calculation only when you have not explicitly defined an LSRPOOL resource definition that corresponds to an LSRPOOLNUM in a file definition. CICS calculates and builds a default LSR pool only when it is opening the first file in LSR mode that references the default pool.
NO
CICS is not to include files opened in RLS mode, and which also specify an LSRPOOLNUM, when it is building default LSR pools. Files defined with RLSACCESS(YES) are ignored when CICS is scanning file entries looking for files that specify an LSR pool it is about to build using default values.

If the LSR pools referenced by LSRPOOLNUMs in your file resource definitions are defined explicitly by LSRPOOL resource definitions, you must specify RLSTOLSR=NO.

YES

CICS is to include in its calculation, when building default LSR pools, files that specify both RLSACCESS(YES) and an LSRPOOLNUM.

Note that an LSR pool built including files that are opened in RLS mode is larger than necessary initially. This option is provided to ensure that, if files are later switched to LSR, the LSR pool is adequate for the extra files. You should specify RLSTOLSR=YES only if both of the following conditions are true:
  • You do not define LSR pools explicitly, relying instead on CICS obtaining a default set of values for you.
  • You have files that are sometimes accessed in RLS mode and sometimes accessed in non-RLS mode (although this is not advised).

The RLSTOLSR parameter is provided to support files that are normally opened in RLS mode, but which can be closed and then switched to LSR mode.

If LSR pools are not defined explicitly using LSRPOOL resource definitions, CICS calculates the resources needed for an LSR pool using default attributes. CICS performs this calculation when opening the first file that specifies an LSR pool that is not explicitly defined. To calculate a default LSR pool, CICS scans all the file entries to count all the files that specify the same LSRPOOLNUM. The size of an LSR pool built dynamically in this way remains fixed until all files that reference the LSR pool are closed. After all files have been closed, another request to open a file with the same LSRPOOLNUM causes CICS to recalculate the size.

If you add files to the system after the LSR calculation has been performed there may be insufficient storage available to enable CICS to open a file that specifies a default pool. This situation could occur if files are opened initially in RLS mode and later closed and reopened in LSR mode. There are two ways to ensure that enough resources are built into the LSR pool to support subsequent switches of files from RLS to LSR:
  • You can explicitly define LSRPOOL resource definitions that correspond to the LSRPOOLNUMs on file definitions, removing the need for CICS to calculate default values.
  • You can specify RLSTOLSR=YES to force CICS to include RLS files when calculating defaults.