March 26, 2001, 4:39 PM —
The largest Linux machine in the world is a big hunk of iron. Mainframe-style
big iron is back in fashion as IBM and independent developers alike have
brought the Linux platform to the S/390 mainframe running within virtual
machines. In his article "S/390: The Linux Dream Machine," Scott Courtney
(see Resources) introduced the S/390 port of Linux and hinted at its
potential as a high-end system to support large clusters of independent
virtual servers for running Linux applications.
For those who think that the mainframe is a dead architecture with limited
potential, you should know that IBM and other vendors now sell more
mainframes than ever before. In fact, the mainframe has flourished alongside
the growth of the Internet as large vendors strive to put their information
systems online and need to expand the capabilities of their mainframe systems
to support the added demand.
So what is this thing called the S/390? What is VM/ESA and LPAR? Where did
such a port come from? For those unfamiliar with the S/390 system but
interested in hearing about this Linux port, this three part series will
explain:
- The S/390 architecture and its origins
- The virtual machine (VM) hypervisor, an important part of the fledgling Linux-for-S/390 community
- The Logical Partitioning facilities (LPAR)
- The two organizations that were concurrently working on ports to S/390
- The I/O architecture, which is the biggest difference between the S/390 Linux port and other ports
- Why you might want to run Linux on S/390
- The applications the community has started running
- A vision, dubbed multiple virtual Linuxes or virtual penguin power, for using Linux in S/390.
