One other item with having LPARs is the storage needed to support the IOCP. If you mimic your entire primary LPAR, you might increase your requirements from 768M to 1024M for HSM storage.
So out of your 8 GB, take out the HSM storage and then storage for the extra LPAR(s). then you can make the decision on whether or not your primary LPAR needs are met. Still might not be a problem, but another thing to consider. Tom Duerbusch THD Consulting On Wednesday 04 January 2006 17:50, Ranga Nathan wrote: > Thanks all for the responses. From the HMC panels I suspected that it is > possible to share IFL across LPARs running z/VM. > I do have a second level z/VM but for realistic tests of RSU, D/R > configurations and training, I feel more comfortable with an > under-resourced test LPAR. > > I understand that if the test LPAR is not up, then the production will > use all the CPU. We have 6GB memory for the IFL. If I give 512MB to the > test LPAR, I think that should be sufficient. May be 784MB if needed. > Current work load is very minimal that even 1GB to the test LPAR would > be quite acceptable. > > Besides, this will allow us to bring up the test linux guests under test > z/VM environment ... > > Tom Duerbusch wrote: > >As others have said, yes, you can define multiple LPARs on the same IFL > >engine(s). Each LPAR will have its own copy of z/VM running. > > > >But....are you sure you want to do that? > > > >When you create a LPAR you have to dedicate resources to it, namely > >real memory. When the second LPAR is not in use, the first LPAR can't > >go over and use the memory (at least without a POR of the LPARs). > > > >But if you give the memory to the first LPAR, and bring up the > >test/disaster recovery VM there, the memory is only used for the second > >level system, when you need it. Hence your first level system has the > >memory at other times. > > > >Now if you have plenty of memory, not a big deal. But if your 1st LPAR > >is paging, it would seem to be a better deal to give the memory to it > >than to carve up another LPAR. > > > >On the other side.... > > > >If the training also includes console functions such as IPLing the > >system, you might want to have the second LPAR for Operator training. > >Just make it real small as no real work would normally be done in it. > > > >(What is the smallest size z/VM can IPL under? No real work, just the > >normal slate of service machines.. > >Seems to me that is use to be under 1 MB.) > > > >Tom Duerbusch > >THD Consulting
