Followup re: VSAM LSR statistics for the archive:
It appears that VSAM LSR keeps certain statistics for each buffer pool from
the time it is created to the time it is deleted. You can get the current
values by using SHOWCB with an ACB that is already OPEN using LSR and that
buffer pool. These are the available stats, according to "z/OS V1R6.0
DFSMS: Using Data Sets":
Field Description
BFRFND The number of requests for retrieval that could be
satisfied without an I/O operation (the data was found in
a buffer).
BUFRDS The number of reads to bring data into a buffer.
NUIW The number of nonuser-initiated writes (that VSAM was
forced to do because no buffers were available for reading
the contents of a control interval).
STRMAX The maximum number of placeholders currently active for
the resource pool (for all the buffer pools in it).
UIW The number of user-initiated writes (PUTs not deferred or
WRTBFRs, see "Deferring Write Requests" in topic 2.8.2.1).
Now I am asking my capacity gurus to find out if these stats are written out
to SMF (or somewhere) at CLOSE or DLVRP or EOJ. When using COBOL programs
and BLSR, it's not like it would be easy to code such a SHOWCB on your own
(possible I suppose, but a lot of trouble to get the ACB from the
[undocumented, OCO] COBOL FILE info, and undoubtedly version and/or release
dependant as well).
Assuming these stats are available from somewhere, it seems to me that the
BUFRDS value can tell me the answer to the question that I originally asked,
namely whether all the buffers in the pool were used in the run. When there
is only one pool in use with only one buffer size, if BUFRDS is less than
the total buffers allocated then some buffers must have been unused. If
greater, then at least one buffer must have been used more than once,
indicating that all allocated buffers were used.
Or better maybe, if NUIW is > zero, then all buffers must have been used,
though that doesn't say much if it is = zero.
Thanks to all for your assistance.
Peter
This message and any attachments are intended only for the use of the addressee
and
may contain information that is privileged and confidential. If the reader of
the
message is not the intended recipient or an authorized representative of the
intended recipient, you are hereby notified that any dissemination of this
communication is strictly prohibited. If you have received this communication in
error, please notify us immediately by e-mail and delete the message and any
attachments from your system.
----------------------------------------------------------------------
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
