CSE551 -- Programming Assignment #1

Out: Tuesday January 18th
Due: Thursday January 27th, before class

For this "warmup" assignment, you will write and run a few microbenchmarks on the operating system of your choice. Here's what you should measure; precisely how you design and implement your measurement code is up to you.

1. System call overhead. (Note: your answer will be in the microsecond time scale.)
   
   
2. The latency to perform a disk seek, or if you're using an SSD or other device that doesn't do mechanical seeks, a random I/O. (Note: your answer will be in the millisecond time scale for conventional disks, and smaller for SSDs.)
   
   
3. The sequential read bandwidth of one disk. (Note: your answer will be in the tens or hundreds of megabytes per second range.)
   
   
4. BONUS: Context switch overhead.

• The department has Linux machines available for your use. Keep in mind these machines are used by many people, so if you use those machines for your measurements you will need to make sure your measurement results aren't affected by somebody else's program. I recommend you find a time when no other programs are running, and run your benchmarks then. If this turns out not to be possible (i.e., all the machines are busy all the time), then find another machine to run them on.
  
  
• Since you're registered in a CSE course, you're eligible to download one of various VMware products, like workstation for Linux, or fusion for the Mac. You can use this to create/install a linux machine. Note that you'll be measuring virtual disk seek and virtual disk bandwidth time, and this might not be the same as physical disk seek/bandwidth: it's up to you to figure out what to do to make it the same if you go down this path.
  
  
• If you take measurements on a shared machine, you need to make sure your benchmarks aren't too disruptive. Your benchmarks have no need to run for more than a few seconds or tens of seconds...
  

What to turn in

• A very short description of your measurement design -- no more than a handful of sentences on each measurement.
  
  
• A very brief description of any limitations to the approach you chose. Again, no more than a handful of sentences.
  
  
• Your results.
  
  
• Your source code (in whatever language or scripting environment you used).