Two more processors added and no benefit. - IBM AS400

This is a discussion on Two more processors added and no benefit. - IBM AS400 ; Hi All, just added two more processors to a machine, so doubling processing capacity. The run time for dayend processing has not changed though. The subsystem dayend is run in, has plenty of main storage allocated to it. In fact ...

+ Reply to Thread
Results 1 to 7 of 7

Thread: Two more processors added and no benefit.

  1. Two more processors added and no benefit.

    Hi All,
    just added two more processors to a machine, so doubling
    processing capacity.

    The run time for dayend processing has not changed though.

    The subsystem dayend is run in, has plenty of main storage
    allocated to it.

    In fact it's on calc and as dayend no users on system.

    Can anyone point me at what to look at, to see why no
    improvement in run time?

    Kind Regards

    Ian

  2. Re: Two more processors added and no benefit.

    Ian wrote:
    > Hi All,
    > just added two more processors to a machine, so doubling
    > processing capacity.
    >
    > The run time for dayend processing has not changed though.
    >
    > The subsystem dayend is run in, has plenty of main storage
    > allocated to it.
    >
    > In fact it's on calc and as dayend no users on system.
    >
    > Can anyone point me at what to look at, to see why no
    > improvement in run time?
    >
    > Kind Regards
    >
    > Ian


    Is the dayend single threaded i.e. one jobq or one job running programs
    sequentially? If so, you won't benefit...


  3. Re: Two more processors added and no benefit.

    On Apr 21, 5:52 am, Ian wrote:
    > Hi All,
    > just added two more processors to a machine, so doubling
    > processing capacity.
    >
    > The run time for dayend processing has not changed though.


    It's hard to answer without significant insight into the processes but
    there are many factors that affect job throughput and processing
    capability is only one. If your jobs are very disk IO dependent for
    instance, adding processors won't make a great deal of difference.
    Analysing performance data should give a greater insight into the
    bottleneck.

  4. Re: Two more processors added and no benefit.

    Nothing can correct poor DB design, bad code, or ill planned security.

    --
    Doug


    "Ian" wrote in message
    news:c72996c2-9a14-4076-bc8e-17c0526ced29@f63g2000hsf.googlegroups.com...
    > Hi All,
    > just added two more processors to a machine, so doubling
    > processing capacity.
    >
    > The run time for dayend processing has not changed though.
    >
    > The subsystem dayend is run in, has plenty of main storage
    > allocated to it.
    >
    > In fact it's on calc and as dayend no users on system.
    >
    > Can anyone point me at what to look at, to see why no
    > improvement in run time?
    >
    > Kind Regards
    >
    > Ian




  5. Re: Two more processors added and no benefit.

    On Apr 20, 7:43*pm, gb wrote:
    > Ian wrote:
    > > Hi All,
    > > * * * * just added two more processors to a machine, so doubling
    > > processing capacity.

    >
    > > * * * * The run time for dayend processing has not changed though.

    >
    > > * * * * The subsystem dayend is run in, has plenty of main storage
    > > allocated to it.

    >
    > > * * * * In fact it's on calc and as dayend no users on system.

    >
    > > * * * * Can anyone point me at what to look at, to see why no
    > > improvement in run time?

    >
    > > Kind Regards

    >
    > > Ian

    >
    > Is the dayend single threaded i.e. one jobq or one job running programs
    > sequentially? If so, you won't benefit...- Hide quoted text -
    >
    > - Show quoted text -


    The dayend is single threaded.

    On a development box did the same thing and dayend time halved.

    Was not expecting improvement to be so drastic but was hoping for
    something.

    Thanks for input.

    Kind Regards

    Ian

  6. Re: Two more processors added and no benefit.

    Have you ensured that the processors have been enabled for your
    partition and that the correct entitlements have been entered?

    "Doug" wrote in message
    news:480be423$0$9523$4c368faf@roadrunner.com...
    > Nothing can correct poor DB design, bad code, or ill planned security.
    >
    > --
    > Doug
    >
    >
    > "Ian" wrote in message
    > news:c72996c2-9a14-4076-bc8e-17c0526ced29@f63g2000hsf.googlegroups.com...
    >> Hi All,
    >> just added two more processors to a machine, so doubling
    >> processing capacity.
    >>
    >> The run time for dayend processing has not changed though.
    >>
    >> The subsystem dayend is run in, has plenty of main storage
    >> allocated to it.
    >>
    >> In fact it's on calc and as dayend no users on system.
    >>
    >> Can anyone point me at what to look at, to see why no
    >> improvement in run time?
    >>
    >> Kind Regards
    >>
    >> Ian

    >
    >




  7. Re: Two more processors added and no benefit.

    On Apr 20, 12:52 pm, Ian wrote:
    > Hi All,
    > just added two more processors to a machine, so doubling
    > processing capacity.
    >
    > The run time for dayend processing has not changed though.
    >
    > The subsystem dayend is run in, has plenty of main storage
    > allocated to it.
    >
    > In fact it's on calc and as dayend no users on system.
    >
    > Can anyone point me at what to look at, to see why no
    > improvement in run time?
    >
    > Kind Regards
    >
    > Ian


    Ian, Look at the collection services file QAPMJOBWT, at V5R3 this
    file contains 16 wait buckets, 16 fields for each wait time and 16
    fields for each wait count. A description of each bucket can be found
    in the file QAPMJOBWTD. You can query these files by job and see
    exactly where your job(s) are spending a majority of their run time.
    This will help you understand where the wait time is and why adding
    the additional processors did not help. IBM also has another product
    called iDoctor for iSeries Job Watcher that allows you to get even
    more granular than what Collection Services goes. Job Watcher at V5R3
    and higher maps these waits into a total of 32 different wait buckets
    and 199 wait enums within these buckets. So you can really get a very
    good view of the job(s) run/wait signature and where you need to focus
    your analysis.
    It was also mentioned in previous posts that CPU is only resource
    where your job(s) could be spending time. I would also like to point
    out that by just adding processors without upgrading the memory could
    cause an imbalance and move the resource contention to memory.

    Additional information on QAPMJOBWT can be found by searching info
    center:
    http://publib.boulder.ibm.com/infoce...v5r3/index.jsp
    Additional information on Job Watcher can be found on the IBM iDoctor
    website:
    https://www-912.ibm.com/i_dir/iDoctor.nsf

    If you still have problems or questions I would suggest opening a
    software problem with your software service provider.

    Regards,
    Tom

+ Reply to Thread