"It depends" definitely fits here. I would say at this point of the JESes and z/OS, that probably 70-80% of the code is common between them. JES3 has the GLOBAL concept of managing the environment, while JES2 is a collection of LOCAL environments. With MAS, JES2 has certainly become more global in nature. JES3 does have a lot of features over JES2, if you plan to use them. Most sites that I have seen running JES3 run in "JES2 mode". JES3 does have the pre-setup requirement, can have up to 255 unique Job classifications, has a built-in Job Scheduler, and definitely has a bit different JCL coding requirements (nothing that can't be overcome). From an operator perspective, JES3 may be a bit more challenging to run (no emails from the seasoned JES3 folks). Many sites that run JES3 are left over from historical environments, and have never changed. You can still find several shops with a single or dual JES3 Global/Local setup. In my opinion this might be a waste of JES3 capabilities. You really need to decide what your JES needs are, and then the right one will fall out for you. And your mileage WILL vary.
zNorman -----Original Message----- From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf Of Lizette Koehler Sent: Monday, September 06, 2010 Monday 4:45 AM To: IBM-MAIN@bama.ua.edu Subject: Re: JES2 vs. JES3 I am sure there will be some opinions on this. But the basic functions of JES2 and JES3 are different. I have only used JES2 and know very little of JES3. So I am a little biased. JES3 has resource functions where JES2 does not. In JES3, as I understand it, a job cannot get into the system unless all allocations are met. However, you can submit a job to JES2 and it could begin to run without all allocations (dasd, tape, etc.) being available. To handle that problem in JES2 you have add-on products like ThruPut Manager, DTS Software SCC, ACS, and so on. So to me the bottom line is more like: JES2 comes with the operating system, but how many more products do you need to add-on before it behaves (okay I will say it) like JES3? I like JES2 because it is simpler in concept than JES3. However, both products have their pros and cons. I am not sure that this can be a apples to apples type of choice. They are both apples, but do you like sweet ones or tart? Do you like Washington or Delicious? Do you like Red or Green? I think it all comes down to what you have worked on and how you have adapted to using it. Both are good systems and do their jobs very well. Lizette ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
