If you are doing sequential reads and writes, half track is the best you can do. If you are random reading small records, I.E. 80 byte, 400 bytes, 2000 bytes; then smaller blocks lead to less I/O per record, since you aren't using most of the data read, and the larger the block the less you use. VSAM use a 4K physical record unless you specify a very large CI size.
On Wed, Nov 23, 2022 at 11:56 AM Paul Gorlinsky <p...@atsmigrations.com> wrote: > > Short block more efficient? Elaborate please. Space utilization and efficient > are not necessarily the same. Latency issues vary a lot depending on the > exact box being used for DASD. DS6K v DS8K. DS8K with rotating v solid-state > ... > > QSAM v BPAM v BSAM v etc... > > General guidelines ... > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
