[comp.sys.sun] Getting reasonable swap performance

chudnall%pkg@mcc.com (11/30/90)

I have a user who is running extreme cpu/memory/disk intensive design
software. I can't elaborate extesively on the software in question (it's
proprietary), but a typical process can take up anywhere from 30 to over
70 Mbytes of virtual memory. The platform he's using is a Sun 4/390 with
56Mb RAM, and 500+Mb swap, running SunOS 4.0.3. For all practical
purposes, it is a single user machine. The problem we're having is that
only about 10-20Mb of the process will stay resident in memory, even if
there is plenty of space; i.e. in one case, the process was taking up 70Mb
of virtual memory, and all but 11Mb of that was swapped to disk, even
though there had to be at least 30Mb of RAM unused, even taking into
account the size of the few other processes on the system. 

My question is: How do we get the system to effectively utilize the
availiable memory for this large process? I am convinced that the slowdown
we're seeing (which happens when the process starts to get large) is due
to the constant waiting on disk to swap pages in and out. We are capable
of purchasing enough memory to handle the largest processes, but I don't
see any point to this when the existing memory isn't being used. Has
anyone else had a situation like this? 

Please respond directly to me: I'll summarize.

Thanks,

--Christopher