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vparmodify on the fly to add more memory

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vparmodify on the fly to add more memory


I have one HPUX system with 3 vpars and I would like to add 5 GB memory to one of them on the fly , without shutting down the target server. Is this possible ? This server has 8 GB memory now .

Iam not moving memory from the other vpars . Iam using the ILM available memory .

#can I run the following command from another vpar when the target system is up and running ?

# vparmodify -p server2 -a mem::5120

Your help is greately appreciated and points guranteed .

rgds/ KJ

Jim Walls
Trusted Contributor

Re: vparmodify on the fly to add more memory

Read the man page for your OS version. Certainly, for HP-UX 11.23 you need to take the target vPar down first.

To quote from the vparmodify man page:

A vp_name in the monitor database must be in the Down state to add or delete resources, with one exception: CPU resources can be added to or deleted from a running virtual partition. This restriction may be relaxed for other types of resource management in a future release.

Steven E. Protter
Exalted Contributor

Re: vparmodify on the fly to add more memory


We are using 5.04 and vpar 5.0.5 and so far, you can move cpu's on the fly and you can't move memory without downing the system.

Maybe this feature is planned for the next release of vpar software, but I don't know anything about that.

Sorry, gotta have some downtime to do it now.

Steven E Protter
Owner of ISN Corporation
Don Morris_1
Honored Contributor

Re: vparmodify on the fly to add more memory


Short version -- only HP-UX 11i v3 supports online memory migration, the vPar version required is A.05.xx or higher.

As long as you meet those requirements, there should be no problem - and yes, that's the command syntax if you want to add the memory as Base (not able to be removed from the vPar later). If you want to make it where you can remove it later (Floating memory), the command would be:

vparmodify -p server2 -a mem::5120:f

Floating memory is only going to be usable primarily by User space, so if this addition is to satisfy an urgent kernel requirement, it probably should be Base. [If Floating is present some of the non-kernel Base usage will migrate automatically to Floating if any is available and the kernel believes the amount of Base is getting low to prevent kernel memory exhaustion].