Skip-sequential processing

When possible, CICS uses VSAM skip-sequential processing to speed browsing. Skip-sequential processing applies only to forward browsing of a file when RIDFLD is specified in key form.

CICS uses it when you increase the key value in RIDFLD on your READNEXT command and make no other key-related specification, such as KEYLENGTH. In this situation, VSAM locates the next wanted record by reading forward through the index, rather than repositioning from scratch. This method is faster if the records you are retrieving are relatively close to each other but not necessarily adjacent; it can have the opposite effect if the records are far apart in a large file. If you know that the key you are repositioning to is much higher in the file, and that you can incur a long index scan, you might want to consider using a RESETBR command which forces a reposition from scratch.