Assignment 1

Assigned: 2/14/95
Due: 2/23/95

Part 1


In this introductory part of the assignment you will be introduced to:
1) The x-windows handshake:

On the workstation running your X window server (probably the machine on your desk) execute the command "xhost + scout.lcs.mit.edu cm51.lcs.mit.edu cm52.lcs.mit.edu" This will allow X Window applications running on scout and two of the partition managers (more about them later) to display on your screen.

On scout execute the command "setenv DISPLAY machine:0" where "machine" is the name of the workstation that is running your X Window server. This will let X Window applications running on scout know that they are to display on your screen.

2) CMview is an application that provides a graphical user interface to Thinking Machine's on-line documentation. Start CMview by executing the command "cmview &". After a short delay a window welcoming you to CMview should appear on your screen.

3) During the day the CM-5 is configured as two 32-node and one 64-node partitions. At night (from midnight to 7:00 AM) it is configured as a single 128-node partition. In other words, during the day the CM-5 looks as if it is three separate machines, two with 32 nodes and one with 64 nodes. At night it looks like a single 128 node machine.

4) DJM is a job manager that assigns CM-5 jobs to these partitions in an intelligent manner. It tries to balance the loads of the various partitions. Using the information you give it, it also tries to avoid running jobs at the same time on a given partition if the total memory used by the jobs is greater than the total memory available on that partition. This is done to avoid runtime failure of a program that requests more memory than is available.

5) Prism is a graphical programming environment that supports program development, debugging, and performance evaluation.

Using CMView, pop up the manual (click on *manuals*) "Using DJM on the CM-5" (under GENERAL). WARNING: There are a few oddball displays on which this does not work. If you have a problem try another display. ANOTHER WARNING: You will soon have lots of windows on your screen. You can close them as you are done with them by pulling down the FILE menu.

Use the page turning icon to go to page iii of the manual and then click on the "index" entry in the table of contents. Now click on the "Prism" entry in the index. Using the hypertext capability of CMview, jump to the section of the manual referred to by the entry (This is on page 34 of the manual).

After reading this section of the manual (there may be things you won't understand - that's OK), click on the "File" button at the top of the window and select the entry "New Window" from the pulldown menu that appears. (The only way to get two simultaneous views of the text in the manual is by creating a new window.) To understand the options in the script file that is presented in this section of the manual, scroll back (or click on the Page button right below the File button) to page 19 in the newly created window and look them up in the table that begins on that page (note that cpu is an abbreviation for cputime and mem is an abbreviation for memory).

6) Create a little DJM script (based on the model on page 35) that will run on a 32 node partition, uses less than 50 megabytes of memory, and requires less than 1 minute of cpu time. Use your favorite text editor to create a script file that will run Prism using these values for the jsub options. Make the script executable using the command "chmod u+x filename", where "filename" is the name of the script file.

7) As described in the DJM manual, use the jrun command to execute the script file you created in Step 6. After a short delay a Prism window should appear on your screen.

One student reported an irritation that Prism allocated too many colors. I have never experienced this problem myself.

8) Click on the button labelled "Help" in the upper right-hand corner of Prism's display and select "Tutorial" from the pulldown menu that appears. Work through all of the tutorials except the last (Customizing Prism).

Continue to part 2.
Return to the class home page.