The KEYLENGTH parameter in the file definition in the CSD, or the MAXKEYLENGTH in the LSR pool definition specifies the size of the largest key to be used in an LSR pool.
The maximum keylength may be specified explicitly using the KEYLENGTH parameter in the file definition on the CSD, or it may be left to CICS® to determine from the VSAM catalog. For more information about the CSD, see the CICS Resource Definition Guide.
The KEYLENGTH parameter causes the "placeholder" control blocks to be built with space for the largest key that can be used with the LSR pool. If the KEYLENGTH specified is too small, it prevents requests for files that have a longer key length.
The KEYLENGTH parameter can be used in CICS systems with VSAM data sets.
See VSAM tuning: general objectives.
The key length should always be as large as, or larger than, the largest key for files using the LSR pool.
The size of the maximum keylength is defined in the KEYLEN parameter in the file definition on the CSD. For more information about the CSD, see the CICS Resource Definition Guide.