I agree of most of the points, but there is a lot more to memory for VM than 64 MB, but that is up to you.
1. You will have a duplicate area for MDC. I don't know. Are you planning on decreasing MDC on LPAR0 to give to LPAR1 or just duplicate it. I use 100 MB for MDC on each of two LPARs, but without a performance tool, I don't know if I have over allocated it or under allocated it. 2. Expanded Storage. You need some if you are a VM paging environment. Did you reduce the size on LPAR0 to give to LPAR1? Or not? If you are talking about 25% of storage for expanded storage, that dwarfs any other VM usage of storage, well other than paging. VM only needs 2 3390-3 drives....that is until you add 5-6 paging packs, and a couple spool packs, and don't forget SFS packs (I keep SFS space on their own packs). And there may or may not be a "dump" pack as well as "t-disk" pack(s). Back on storage, with poor planning, you can end up with another GB of memory for overhead functions. That might be painful. Tom Duerbusch THD Consulting >>> "Romanowski, John (OFT)" <john.romanow...@cio.ny.gov> 7/22/2009 2:49 PM >>> I have a site like you describe: 2 z/VM LPARs sharing all the IFLs, also sharing channels to dasd, tape, etc. One LPAR for test/development Linux guests, the second for production linux guests. The PRSM overhead seems negligible, 0.5-0.6%. The memory for linux guests dwarfs the memory needed to run z/VM OS, 64M or whatever the manual says now for z/VM. We give the production LPAR a higher partition weight than test/dev LPAR and more central and expanded storage than the test/dev LPAR. We find the extra work/complexity of maintaining 2 z/VM LPARs is outweighed by the benefits of isolating the workloads and being able to schedule outages on each LPAR independently of each other. > -----Original Message----- > From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On > Behalf Of Mark Jacobs > Sent: Wednesday, July 22, 2009 1:18 PM > To: IBMVM@LISTSERV.UARK.EDU > Subject: Multiple zVM Lpars - Resource consumption > > Can anyone give me an estimate on additional resource consumption if we > take one z/VM lpar with 'x' IFL's, 'y' GB of memory and 'z' Linux > guests > and we create an additional z/VM lpar sharing some/all of the IFL's, > taking some amount of the memory and some of the zLinux guests. > > I know that we will have some amount of PRSM overhead and there will be > some increase in real storage needed for the additional z/VM operating > system and some additional DASD requirements. I'm looking for some > numbers I can take to management and if I missed something for the > additional resources needed to support the new z/VM lpar, > > -- > Mark Jacobs > Time Customer Service > Tampa, FL > ---- > > You can have any kind of a home you want. You can even > get stucco. Oh, how you can get stucco. > > Groucho Marx - The Cocoanuts (1929) This e-mail, including any attachments, may be confidential, privileged or otherwise legally protected. It is intended only for the addressee. If you received this e-mail in error or from someone who was not authorized to send it to you, do not disseminate, copy or otherwise use this e-mail or its attachments. Please notify the sender immediately by reply e-mail and delete the e-mail from your system.