David, >Ted, I would disagree with your point (2) in one case. > For a VSAM dataset with the allocation coming from IDCAMS DEFINE > parameters, the primary is >remembered in the catalog listing. If the file > is defined in a non-guaranteed-space environment with more than >one volume > specified, the allocation succeeds only if the primary amount can be found on > enough volumes. >All volumes except the first one are placed in CANDIDATE > status, and the space is not allocated. During >file load, when it attempts > to go to one of the candidate volumes, it goes after the primary amount on > the next >candidate volume, and the job fails if it is no longer there. > As a note, we always defined these multi-volume VSAM files with zero > secondary so that they could >not eat all the extra space on the volumes. It > is possible that this '0' secondary affects the behavior with the >candidate > volumes.
Regular old fashioned vsam datasets always use the primary allocation amount for the first allocation on a volume. Extended vsam can use primary or secondary amount when extending to a second or later volume depending on the additional amount setting in the dataclas that Darth refered. If the storage class has guaranteed space = yes, the primary amount is allocated on all volumes. If the storage class has guaranteed space=no then only one volume actually is allocated and all remaining candidates have a single asterisk (*) as the volser. Once you write enough data to the vsam dataset and it needs to extend to another volume, SMS selects a volume at that time. You only have a volser on a candidate volume if the vsam dataset is not sms-managed. Regards, John NOTICE: The information contained in this electronic mail transmission is intended by Convergys Corporation for the use of the named individual or entity to which it is directed and may contain information that is privileged or otherwise confidential. If you have received this electronic mail transmission in error, please delete it from your system without copying or forwarding it, and notify the sender of the error by reply email or by telephone (collect), so that the sender's address records can be corrected. ---------------------------------------------------------------------- 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
