Is there precedence between Dialog and Batch jobs?

[former_member84834]

This is a purely theoretical question, but I was wondering if I have a batch job and a dialog job running does SAP give more resources to the dialog job? Does SAP have a concept of precedence for batch jobs versus dialog jobs? I have expierence with the UNIX work and there is a concept of "nice". A process with a higher "nice" value gets a larger chunk of the CPU time than a lower priority process. I would think that batch jobs would have a lower "nice" value than a dialog job in SAP, but I do not know if they have anything like this concept.

[Former Member · Accepted solution]

Hello my friend

DIA work processes run dialog jobs and BTC work processes run batch jobs, both type processes have the same priority to OS. However, background work process is different from dialog work processes in two ways:

1. A dialog work process has a run-time limit that prevents users from interactively running especially long reports. By default, the system terminates any dialog work process in a transaction that exceeds 300 seconds. Although the value of the limit can be changed (in the system profile parameter rdisp/max_wprun_time), that limit is always in effect for dialog work processes. No such limit applies to background work processes.

2. Background work processes allocate memory differently than dialog work processes so that background work processes can become as large as they need to in allocated memory to allow for processing large volumes of data.

Having special work processes for background processing provides an additional dimension for separating background processing and interactive work. Typically, background processing and interactive work on the system is separated by time of day. For example, interactive users have the system during the day, large background jobs have the system by night. But the background work process also lets you separate interactive from background use by server, since background jobs can only run on those servers that offer background work processes.

Regards,

Effan

[Former Member]

I checked a few systems, on HP-UX every workprocess had a nice value of 20. On SLES 10, they all have a value of 0.

So no, there is no distinction in the nice values between a dialog an a batch process.

Cheers Michael