Adam Thornton writes: > On Tue, 2004-06-22 at 10:58, Walter Wojcik wrote: > > Does anyone have experience running zLinux in an LPAR which has multiple > > CPUs defined? We have experienced negative performance characteristics > > with Intel Linux versions (RedHat, SUSSE) when the Intel machine had 4 > > processors. We were wondering if the same performance degradations appear > > on the mainframe. > > Without addressing your actual question at all: > > If you need 4 engines in an LPAR, I would question whether the zSeries > is the right tool for the job. You're clearly doing something pretty > computationally-intensive at that point, and machine cycles on other > hardware are generally a whole lot cheaper. I'd take a look at the app > design and see if there isn't some way to offload the CPU-intensive > stuff to a different box, and keep the I/O-intensive stuff on the > zSeries.
Both the original question and this response are rather ambiguous. I suspect that when Adam refers to "4 engines in an LPAR", he is thinking of Linux running by itself (no z/VM) in that LPAR and that he assumes the original poster means the same. When I read the original question, I assumed it was just a question about scalability and that the LPAR would be using z/VM to run multiple Linux guests, some of which may, at times, want to peak at using 4 CPUs. Provided the sizing is done properly and any such peaks "separate out" nicely, I would imagine zSeries would do a very good job given the excellent "raw" scaling capability of zSeries (as others have said) and the wonders of z/VM to provide such "time-shift" sharing. If the original poster really did mean a 4-way LPAR with Linux running "native" in it, then my response is irrelevant of course (though I can still think of some interesting configurations: some CPU-intensive applications may simply need all that CPU in order to drive even larger amounts of I/O that the hardware is good at). --Malcolm -- Malcolm Beattie <[EMAIL PROTECTED]> Linux Technical Consultant IBM EMEA Enterprise Server Group... ...from home, speaking only for myself ---------------------------------------------------------------------- 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
