15-347 Spring '98
Class Alpha Systems
Availability
We will be using Alpha processors extensively in this course. Every
student should have an account that will work on any of the machines.
Finger yourself at black.ece.cmu.edu to find out if you
have an account and to determine your login ID.
These machines can be reached remotely via any internet connection.
They live off in some machine room and don't even have consoles. They
can act as X window clients, however, so you can treat them the same
way as the Andrew Unix servers, (except that they're a lot faster. :)
These machines work from an AFS account set up for you in domain
ece.cmu.edu. You can navigate between this account and
your andrew account using standard AFS operations. You can use
klog to authenticate yourself from one domain to another.
Below is a list of Digital Alpha DPW433 Workstations available for
class use. Please note that
black.ece.cmu.edu
is the lead machine in the group and the password file is copied from that
machine to all others each night so if you make a change to your
default shell, etc you need to make that change on black.
Password changes should be made using the kpasswd command and they
will take effect immediatly on all machines in the group.
You can click on any of the following machine IDs to establish a
telnet session. If you want to run any X window applications, you
should also execute the command xhost XXX.ece.cmu.edu on
you local machine, where XXX is the name of the machine to
which you connected.
Eventually we will provide a system to help you connect to the least heavily
loaded machine. For now, you can use the following experimental script
(generously provided by Prof. Phil Koopman in ECE) to observe the number of
users logged into each of the machines:
http://ballista.ece.cmu.edu:8080/koopman/color_machines.cgi. Note that
this is not a "load" number, but just the number of logged in users.
ECE facilities is working on a fancier solution, but this
should be helpful for now.
Performance
The machines we're using for class have the following characteristics:
- Based on DEC Alpha 21164 CPU.
- Our clock frequency program measures them at 433 MHz
- The timer interval (delta) is .976 milliseconds (very short!)
I've done some benchmarking of the matrix multiplication example
presented in class on Feb. 5. The results are described on the Alpha measurements web page.
Documentation
We'll be working with these machines at a fairly low level of detail. Useful documents include:
- Our own Alpha Assembly Language Guide, available in Postscript and PDF format.
- NOTE (2/23/98): Figure 1 diagramming the program stack,
and the associated text have been revised.
- NOTE (2/20/98): An earlier version of this guide had a typo in
Table 2 regarding the operation of "scaled" add and subtract instructions (i.e.
s4addq, s8addq, s4subq, and s8subq).
In particular, it is the first source operand (rather than the second)
which is multiplied by 4 or 8 in these instructions.
- Digital's Assembly Language Programmer's Guide
available in Postscript and PDF format. This document is 238 pages long. If you insist on killing trees, please print out the
Two sheets per page postscript version.
- Digital's Alpha AXP Architecture Reference Manual
available in PDF format.
This document is 352 pages long and it contains lots of esoteric stuff
that we don't care about for this course. It also doesn't document
some of the more recently added instructions, e.g., integer divide.
Still, it provides the definitive reference for the different
instruction types and formats.
Randy.Bryant@cs.cmu.edu, last updated 26 February 1998.