IBM Mainframe Forum

Hi all,
How to find the setting of maximum number of jobs that are allowed to run concurrently on a z/OS system?

all depends on Your definition of job
job in a strict meaning or in wider sense
as ... JOB, STC, TSO ?

for JOBs in strict sense the limit is the number of initiators
for TSO users the number is defined by the MAXUSERs TSO parameter
for STC( IIRC ) theoretically no limit

the best places to look for such info are
for the supported values ... the manuals
starting from
http://www-03.ibm.com/systems/z/os/zos/ ... index.html
and search for the INITIALIZATION guides

for the values used in Your organization ... Your suppoort

enrico-sorichetti wrote:all depends on Your definition of job
job in a strict meaning or in wider sense
as ... JOB, STC, TSO ?

for JOBs in strict sense the limit is the number of initiators
for TSO users the number is defined by the MAXUSERs TSO parameter
for STC( IIRC ) theoretically no limit

the best places to look for such info are
for the supported values ... the manuals
starting from
http://www-03.ibm.com/systems/z/os/zos/ ... index.html
and search for the INITIALIZATION guides

for the values used in Your organization ... Your suppoort

Oh..Thanks. Is there any setting contained in IEASYSxx PARMLIB members?

Is there any setting contained in IEASYSxx PARMLIB members?

why not look Yourself at the manuals ?

YGNHZEUS wrote:Oh..Thanks. Is there any setting contained in IEASYSxx PARMLIB members?

No. The nearest specification in IEASYSnn is the maximum number of address spaces, which is not quite what you are looking for.

Not a lot to do with memory. Just count the number of initiators then deduct those that are running system tasks eg IMS CICS DB2 etc. The remaining initiators are available for jobs of the right class. May years ago - mid '80s - whilst new mainframes were being installed I think the .limit was 1024 initiators but for effective throughput of batch we actually fired up about 30 or 40 including those for system tasks.