Chapter 3. Operating NetView FTP V2.2.1 MVS - IBM

Example 3: CSAELIM value = (RECSIZE - 1148 bytes)
This CSAELIM value is acceptable for installations where requests that need an
RXB occur rarely, and the saving in CSA storage is worth the risk of an occasional
queuing bottleneck.
Example 4: CSAELIM value < (RECSIZE - 1148 bytes)
CSAELIM values in this range are not recommended, for the following reasons:
� DASD space is wasted.
� Frequent queuing bottlenecks can occur.
� Requests whose required RXB is greater than the CSAELIM value might never
be processed.
It is the system programmer’s responsibility to ensure that the amount of CSA
storage specified in the CSAELIM parameter value is available. The amount of
storage required for each FSBX must be contiguous, but FSBXs need not be contiguous
to each other.
If sufficient CSA storage cannot be allocated when the queue handler attempts to
carry out a command, the following occurs:
ADD The request is rejected.
QUERY The request is processed without additional CSA storage.
OBTAIN The request is deferred.
NOTIFY The RXB on the request queue is not updated.
STATUS The display is truncated.
When the queue handler is started or restarted, and the request queue directory is
rebuilt, all requests that need an RXB are checked to see if they are dispatchable.
If the CSAELIM value is less than the RXB size for a request, then the CSAELIM
value must have been decreased since the request was added to the queue; in this
case the request is marked as blocked and does not become dispatchable until the
CSAELIM value is increased to a value greater than the RXB size.
Appendix D. Storage Requirements 207