Work Load manager usage

UNIX AIX
1

Dear All

I am studying on system resource control matter.
I know ulimit utility can done the job well.
However,I want to clarify that whether workload load manager work in VM environment only.

For example
I have an AIX machine(not VM), can I use work load manager to limit user resource (such CPU time,network traffic)?
If so, can I assign user or group to a workload partition?

thank you very much

2

Hi,

i hope i understand your question correctly.

The Workload Manager (WLM) is part of the AIX kernel and controls the resources of a standard AIX installation as well as the resources of Worload Partition (WPAR).

WLM works with classes, e.g. system, default, etc. and these classes can be limited or prioritized for CPU, Memory, diskIO and Process:

General characteristics of a class
CPU resource management
Memory resource management
diskIO resource management
Process total resource management
Class total resource management

You can not directly assign a limitation for a specific user but you can assign a user (more specifically all commands from a user) to class, which is limited.

 #  Class     User      Group     Application             Type      Tag
001 System    root      -         -                       -         -
002 Default   -         -         -                       -         -

I have not worked yet with WPARs but if i understand it correctly the (ressources of) WPAR is controled from the host system via WLM.

I hope the is what you ask for.

Regards

1 Like
3

WLM is an extremely different approach to resource control than ulimit.

WLM is meant to be a policy-based control mechanism managing access to resources over time - while ulimit sets hard maximum amounts of resources.

With ulimit you have, basically, unregulated access to all resources until one of the resources reaches it maximum, then the process stops. With WLM you set target ceilings - when a target is reached access to resources may be postponed until the utilization (usually a percentage) is below target and access is granted again.

Hope this helps!

1 Like
4

-=XrAy=- : do you mean through WLM, administrator can assign amount of resource for an executable file only?

5

Yes,

you can assign a executable to an class and limit the ressources of these class.

Here an example configuration:

 #  Class     User      Group     Application             Type      Tag
001 Test      -         -         /usr/bin/ksh            -         -

  Class name                                          Test
  Maximum amount of CPU time                         [-] 
  for each process in the class
  CPU time unit                                       
  Maximum amount of DiskIO                           [-] 
  for each process in the class
  DiskIO unit                                        [KB]
  Maximum amount of activity time                    [-] 
  for a login session in the class
  ConnectTime unit                                   
  Maximum Amount of Virtual Memory                   [-]
   for each process in the class
  Virtual Memory Unit                                [MB]

Regards

1 Like
6

Thank you for your effort

One more question, is it possible to assign more than 1 class to the same executable?
If possible, how the workload manager handle this situation?

Thank you in advance.

7

Hi,

a executable can only be assigned to one class but you can switch the class whenever you want.

Regards

1 Like
8

Oh I c

thank you very much