255? Really?
Bob
-------------------------<snip>-------------------------
The PDS directory records are a fixed size, LRECL=255, I believe. My
reason to allocate a PDS filling a track, or multiples, with the
directory comes from thinking half-track blocking is efficient for reads
and if I use one half, or full track directory then I am doing the least
amount of I/O as possible. Reality may be different. The optimum number
of PDS entries to allocate depends on the type of PDS, loadlib or other.
For other, are statistics kept or not. How many of us ignore taking the
time to plan the need and just allocate with a larger number than we
need? I chose to allocate larger based on number of tracks. I no longer
use a PDS for non-loadlib datasets.
--------------------------<unsnip>-----------------------
Ken, the physical BLKSIZE of the directory is 255, plus a 8-byte
physical key. You can set a PDS BLKSIZE to any value you like, but it
will have NO effect on the directory characteristics. On a 3390, that
means that you will always get 45 directory blocks to a track, or 44
blocks plus the EOF mark.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
