Which is better vPAR or WLM/PRM

[Shivkumar]

Dear Sirs,

Is vPAR not preferred for mission critical or production implementation ? Actually, someone said that the vPAR is not preferred for mission critical applications. I was under the impression that vPAR is HP's reply to IBM's DLPAR for on demand computing and virtualization and usually used for mission critical applications.

Appreciate any thoughts.

Thanks,
Shiv

[melvyn burnard · Accepted solution]

They are two completely different things
Vpars allows you to partition a supported server into virtual servers, each running it's own instance of HP-UX.

WLM and PRM are resource managers that run on INDIVIDUAL OS instances, and allow you to manage resources for applications.

Which you use is a decision yopu need to take.

I can recommend the following book as an introduction to all of the Virtual Server Environment from HP:

http://www.amazon.com/gp/product/0131855220/qid=1134150734/sr=1-1/ref=sr_1_1/103-7479428-1657451?s=books&v=glance&n=283155

[Mel Burslan]

considering not all of hp's server line is capapble of doing vPars but WLM capable of working on the OS level, I think these two concepts should not be confused, although at some very basic level you can think of them doing the same thing.

main differentiation of using one or the other to split the resource demands of two or more application instances, should be made depending on the server hardware that one is operating on.

[Shivkumar]

Hello Sirs,

We have model as shown below in our environment:-

9000/800/N4000-55
9000/800/L3000-8x

Thanks,
Shiv

[dirk dierickx]

vpar is like a vmware, you get 2 (or more) virtual machines on one box. that means 2 os's to manage etc.
prm is still one os, but you get control over what/who uses which and how many resources on that one os.

[Srini Jay]

Shiv,
By using vpar you get 'n' virtual servers.
Please be aware that if are going to use vPar, you may have to get additional licenses for all third-party software you are using (especially, if those are based on number of simultaneous users instead of system CPUs).

Using PRM, you can limit the resource (CPU/memory/disk etc) usage by users/processes/applications. In this case you just have only one server and you need not buy additional license.

This (additional licenses)is the only reason I could see for not using vpar on production server.

[Srini Jay]

Shiv,
By using vpar you get 'n' virtual servers.
To my knowledge, if you are going to use vPar, you may have to get additional licenses for all third-party software you are using (especially, if those are based on number of simultaneous users instead of system CPUs).

Using PRM, you can limit the resource (CPU/memory/disk etc) usage by users/processes/applications. In this case you just have only one server and you need not buy additional license.

This (additional licenses)is the only reason I could see for not using vpar on production server.

[Shivkumar]

How WLM and PRM are related to each other ?
Are they different or interlinked ?

[Steven E. Protter]

Shiv,

Original question: The right tool for the right job.

WLM and PRM are complementaary tools, with PRM allowing you flexiblity in assigning priority to various processes or proces groups. A really great, though probably underutilzied tool.

http://education.hp.com/datasheets/u5447s.pdf

For more. A good doc to have lying around.

SEP