SPACE=(10000,1024) means you want enough space to store 1024 blocks, assuming each block is 10000 bytes.
SPACE=(10000,1024),AVGREC=U means you want enough space to store 1024 records, with an average record length of 10000 bytes. SPACE=(10000,1024),AVGREC=K means you want enough space to store 1024K blocks, assuming each block is 10000 bytes. AVGREC only applies when SMS is active. when it is, as documented in the JCL Reference, "The system allocates DASD space in whole tracks. The number of tracks required depends on how the records are blocked. The system uses one of the following as the block length to compute the number of tracks to allocate, in the order indicated: 1. The block size from the DCB parameter, if specified 2. The system determined block size, if available 3. A default value of 4096" I think the system allocates more space when you specified AVGREC=U because it took the default block size when calculating space. It takes more space to store the same amount of data at a 4096 byte blocksize than it does with a 10000 byte blocksize. You could also have specified: SPACE=(1,10000),AVGREC=U to request 10000 bytes or SPACE=(1,10000),AVGREC=K to request 10000 KBytes or SPACE=(1,10000),AVGREC=M to request 10000 MBytes While it may seem strange to request allocation in one byte records, I think this might be what you want to do. Tom Marchant ---------------------------------------------------------------------- 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
