Re: WRKACTJOB still a resource pig?

[Trevor Perry <trevor@xxxxxxxxxx>]

WRKACTJOB (and WRKSYSSTS) has to interrogate the entire set of job control
tables to gather its data. And, it keeps collecting this information until
you sign off - or, some people believe when you use SysReq 2.

WRKACTJOB is a low level system task - and if you have a lot of people using
it, it IS going to step on some actual business work. Sure, you can use the
excuse that it does not matter with the current system speeds, but on
principle, WRKACTJOB and WRKSYSSTS should only be used for researching
system problems. Even then, it is preferable to use the performance data
that is collected for research. And WRKSYSACT, with its priority set to 0,
should only be used under extreme circumstances to resolve issues such as
runaway jobs. All the data you gather from these commands is available using
the performance data collection tools.

Using WRKJOB, WRKSBSJOB, WRKUSRJOB, WRKSBMJOB, WRKSBS are better choices
when you are just wanting to "see how my job is doing".

If you are using WRKACTJOB all day to check performance, it probably means
your server is simply not well tuned for the business requirements. Having a
performance methodology will allow you to balance the server resources among
the business needs, according to the business priorities. Once this is
established, the need for WRKACTJOB disappears.

WRKACTJOB is really only good for seeing what is happening ~right now~, even
if you have it running all day. Any capture of data shorter than a 5 minute
period can be artificially spiked, and any capture longer than 5 minutes
will be artificially flat.

Ultimately, WRKACTJOB is just a habit :-)



On 12/28/07 12:13 PM, "Dan" <dan27649@xxxxxxxxx> wrote:

> In the early, EARLY days of my AS/400 experience, I seem to recall that
> WRKACTJOB was a resource pig, and could adversely affect performance.  In
> fact, there were a few shops I worked in that restricted access to that
> command but had *ALLOBJ authority for everything else by default.  And, I
> also seem to recall that, instead of using F3 or F12 to exit the command,
> you were supposed to use the System Request key, then take option 2 to "End
> previous request"; that way, WRKACTJOB supposedly ceased to run in the
> background.
>
> I also seem to recall that all of this changed somewhere along the way to
> V5R3, so that it is no longer a resource pig, and system performance is not
> adversely affected by someone having it up on their screen all day,
> refreshing it every few minutes or so.
>
> The reason for this post is because I'm getting hammered by an aggressive
> system cop/idiot (how this guy ever got hired here is a complete mystery;
> think Dilbert's Mordac, "Preventer of Information Technology") who thinks
> that our system's performance is in the crapper because I have WRKACTJOB up
> all day when I'm on call for a particular production application, and I
> refresh at 5 minute intervals.  This is on a model 550 with, I believe, 8 GB
> of memory (based on the sum of all Pool Sizes as shown on DSPSYSSTS; I can't
> remember if this is accurate, or whether there is a better source of
> information for this).
>
> Right now, after having a job running this for over two hours, WRKACTJOB
> shows the system's CPU at 70.7% and my job using 0.1%.
>  The total processing unit time used by my job thus far is 10.3 seconds.
> Are there any other metrics that would be useful.
>
> Ammo, anyone?
>
> TIA,
> - Dan