IBM Mainframe Forum

hi,
i had given SPACE=(100,(80,20,RLSE) .But in allocated blocks ,it is given as 78.I wnt to know why this is coming so.
waiting for your favourable response.

regards,
Bineesh

Space is allocated in track units; you cannot allocate less than that. When you specify SPACE=(100,80) z/OS calculates the number of tracks required to hold 80 100 byte records; this works out to 2 tracks. Your program actually wrote less data than that, just 1 track, so z/OS released the 2nd track, as specified in your SPACE parameter. When ISPF displays the space, it calculates the number of 100 byte records that will fit in 1 track and displays 78.

hi
Thanks for your information.But it will be better if you elaborate more on this.
regards,
Bineesh

Hi,

SPACE=(100,(80,10),RLSE) means

8kb of pri space and 15kb of sec space (15 extents). As space can be requested in terms of blocks as numbers, the pri quantity will be measured in bytes.

But 1 track is 56.6kb.

Kindly let me more clear about the track subparameter in this case.

regards,
Bineesh.

See the JCL manual. It will tell you everything you need to know about the SPACE parameter.