At least one aspect of SN is the NoData, that is CP will not save any data of it in the spool. That means when you load it, it will nbe empty. The fact however that it is Shared, means all users see the same data (otherwise it would be "Ex"; Exclusive). What I don't know is if guests are allowed to write into an SN segment (the only usage I know is by CP's Monitor, wheer CP's writing in it, the guest -like PERFSVM and MONWRITE- read from it).
2010/4/12 Leland Lucius <[email protected]> > If I were to define a DCSS as type SN and populate it with a filesystem > full of data, how is z/VM going to share it among several Linux guests? > > I'm assuming that the pages of the DCSS are shared among the guests such > that there's really only one page actually in memory and that every guest is > mapped to that page right? So, what about the pages that are written to? I > understand that for type SW, every guest would see the updated page and > there's still only 1 page in memory. > > But what happens for type SN? If a guest writes to a page, are the updates > visible to the other guests? > > I know, I know...I can just test it myself, but it would be good to hear it > from the ppl that know for sure. > > Thanks, > > Leland > > -- Kris Buelens, IBM Belgium, VM customer support
