> Documentation states that the V-DISK space is created when > the first user > links to it (logon & format) and it is destroyed when the last user > detaches from it (logoff). If I add this same statement to > all the Linux > User Directory entries will they all attempt to share this > area?
No. Each virtual machine with MDISK statement will get a private VDISK. The second and additional users of the disk should have a LINK statement in their directory entry for the MDISK. If so > that has implications on when you format this area, as only > the first Linux > will need to link & format this space. You cannot share swap space between guests. VDISKs are drawn from a pool of memory pages maintained by CP and behave by the same rules as any other minidisk. > 1) V-DISK blocks appear to be 512 byte blocks & are created > in 8-block > pages. True? True. The pages are allocated when written, and may be paged out and stolen if not in use. The size specified is really an upper bound on what a particular VDISK is allowed to use. > 2) Will all Linux guests, that contain "MDISK 300 FB-512 > V-DISK 256000 > MWV" share the same V-DISK space? If so is one 256000 block > area allocated > & shared or (256000 x #-of-Linux's) allocated & all shared? The VDISKs are all allocated from the same memory pool, but they are separate for each virtual machine defining one, just like any other minidisk. > 3) How will you automatically know when a given Linux is the > first and > therefore needs to format the area, if area(s) are shared? Since you can't share swap, the question is moot. All guests must format their own swap disks. > 4) SuperValu Red Paper suggests V-DISK size 15% of VM size, > what's up with > this formula 2 x VM size + 32M ?? My users typically write large-memory applications that can malloc() big chunks of storage at one go. I reserve 32M of swap no matter what (because all the critical linux bits fit easily in that space), and the 2xVMsize allows two users to go berserk allocating memory and still give me time to catch the problem and abort the berserkers without impacting other users on the same instances, as well as keeping the initial testing virtual machine size small while I find out what the actual usage characteristics are. Keep in mind: I *start* with 2x+32M. That's *not* the final configuration. ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
