jdubb@bucsf.bu.edu (jay dubb) (02/07/91)
I am posting this for a friend of mine who doesn't have access to USENET, so please respond directly to mlevin@jade.tufts.edu. What is vmunix and genvmunix (and the difference between them)? Also, what are the alternatives for the argument to the b/3 (boot) command from the >>> prompt? Mike Levin (mlevin@jade.tufts.edu)
alan@shodha.enet.dec.com ( Alan's Home for Wayward Notes File.) (02/07/91)
In article <74094@bu.edu.bu.edu>, jdubb@bucsf.bu.edu (jay dubb) writes: > > I am posting this for a friend of mine who doesn't have access > to USENET, so please respond directly to mlevin@jade.tufts.edu. I'll follow-up and reply to the sender. Once again this is probably of general interest. > > What is vmunix and genvmunix (and the difference between them)? > Also, what are the alternatives for the argument to the b/3 (boot) > command from the >>> prompt? genvmunix is a generic kernel that we ship with the base system. It has drivers and data structures for nearly everything supported, but the proverbial kitchen sink, built into it. About the only thing I know of that isn't included are UDA50 and KDA50 controllers in floating address space and assorted communications devices like DZs, DMFs, DHU, etc that are in predictable locations. It is used as the running kernel during the installation process and by doconfig(8) to build a system specific configuration. vmunix is the ULTRIX kernel itself. Unless the local configuration file has been modified and the kernel rebuilt, it has only those drivers and devices that are on the system. Other interesting differences: o The GENERIC kernel is a single processor system. No SMP support is included. o The generic kernel assumes that the root file system is on the A partition of the boot device and that the ONLY page/swap partition is on the B partition of that device. o MAXUSERS is set to 2. This seriously limits some of the kernel table sizes. o Only 10 processes are allowed for those two users. o It assumes the system is in the U.S. Eastern timezone and that the rules for Daylight Savings Time are in affect. o There are 6 MB of physical memory. I don't think this really has much affect, since the usual check made on physical only cares about the value being greater than 64 MB or not. o The size of the buffer cache is limited by MAXUSERS. o DECnet and DLI support aren't included, but NFS and RPC support are. > > Mike Levin (mlevin@jade.tufts.edu) -- Alan Rollow alan@nabeth.cxn.dec.com