On Fri, 23 May 2008 07:09:42 -0400, David Cole <[EMAIL PROTECTED]> wrote:
>At 5/23/2008 04:58 AM, Ted MacNEIL wrote: >>|Is there an "official" way to enforce job execution sequencing? >> >>JES2 has never guaranteed that jobs will execute in the same order >>as submitted. It depends on how long it takes to convert. > >Bingo. Thanks for jarring my memory. > >So I went to the books (imagine that) and found: > Initialization and Tuning Guide > Controlling JES2 processes > Job selection and execution > Controlling the sequence of job execution > Serial job execution sequence >(aka: >"http://publib.boulder.ibm.com/infocenter/zos/v1r9/index.jsp?topic=/com.ibm.zos.r9.hasa300/has2a360.htm";) > >and relearned that I can specify CNVTNUM=1. (That works for me >because we never use //JCLLIB.) > And because you are a (very) small shop. "With CNVTNUM=1, the system can "hang" depending on the characteristics of the job stream. See z/OS JES2 Initialization and Tuning Guide for more information on job queuing and how to control job execution sequence." >From init & tuning: " JES2 is limited to processing your workload in a serial manner without respect to the types of jobs that are being submitted. Large batch jobs and TSO logons are treated in a similar way. Each of the job's resources are required when the job executes. As such, any migrated libraries and data sets that the job needs, must be restored before the job can execute. The time spent waiting for these migrated resources can backup other jobs in the queues. System hangs and deadlocks can occur in the system. When jobs are waiting for resources that have been migrated, the migration program needs to run and restore these resources. The migration program is often a job that needs JES2 conversion before it running. Since only "1" JES2 converter processor is defined to do the conversion and it is waiting, the migration cannot occur and the system becomes deadlocked. As an example, this condition can occur for jobs that need JCLLIB data sets, which have been migrated by a product like DFHSM. If a job has an exclusive ENQ on a JCLLIB data set and another job needs that JCLLIB data set, the job must wait till the ENQ is released." Mark -- Mark Zelden Sr. Software and Systems Architect - z/OS Team Lead Zurich North America / Farmers Insurance Group - ZFUS G-ITO mailto:[EMAIL PROTECTED] z/OS Systems Programming expert at http://expertanswercenter.techtarget.com/ Mark's MVS Utilities: http://home.flash.net/~mzelden/mvsutil.html ---------------------------------------------------------------------- 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
