CS244 '17 PA3: Mahimahi

Reproducing our reproductions

Here we provide instructions for running the experiment sequentially. Since our measurements take a long time to run, we provide a shorter version with eight websites, running each measurement only five times.

We apologize in advance for the complicated instructions. The complications mostly arise from our reliance on specific Linux kernel features (see the “Challenges” section); this is why we’re providing an image for you to use.

1. Create a Google Storage bucket in your project like this. (You can choose the Multi-Regional storage class and United States as the location.)
2. Download our image here. If it doesn't work, here's another link.
3. Upload our image to your bucket like this. You should now see our image listed in the bucket.
4. Go to the Images page and click on Create Image. Give it a name, choose Cloud Storage File for Source, click on Browse, and locate the image you just uploaded to your bucket. Click on Create.
5. Launch a VM from the VM Instances page (click on Create Instance) with these parameters:

• Zone: us-east1-c
• Machine type: 2 vCPUs (should say 7.5 GB memory by default)
• Boot disk: click on Change, go to the Custom images tab, and choose the image you imported in Step 4; use 20 GB of Standard persistent disk
• Firewall: Allow HTTP traffic
• Click on Management, disk, networking, SSH keys. Under Metadata, enter:
  • Key: serial-port-enable
  • Value: 1
• Click on Create and wait for the instance to be launched.

6. When the instance has been successfully launched, click on the instance name, scroll to the bottom, and click on Connect to serial port.
7. When the console window has loaded, enter fsck /dev/sda1 -f. When asked whether to fix errors, always press y. When fsck is done, close the console window.
8. Click on Reset and wait for a minute or two.
9. Find the External IP on the same page, and ssh into it (user: cs244, password: cs244)

• You can type ssh [email protected] in the terminal and enter the password.
• Alternatively, go back to the VM Instances page and click on SSH next to this instance. After you’re logged in, type su cs244, enter the password, and type cd to go back to the home directory.

10. Type cd cs244-pa3-mahimahi.
11. You’re now ready to run the experiment! The short version may take up to 1.5 hours. To run the experiment in the background, type screen and press Enter, then run ./reproduce.sh. You should see something like:

    DELAY = 100, TRACE = 5Mbps_trace, RUNS = 5
    
    Sun Jun  4 21:54:11 UTC 2017
    Measuring www.ask.com
    Mahimahi raw...
    0
    

12. You can now press Ctrl-A then Ctrl-D to quit screen. Feel free to terminate the SSH connection and come back later.
13. When you come back, resume screen by entering screen -r. If the experiment has finished, you should see a URL for the graph. Go to that URL in your browser. You should hopefully see a similar but coarser-grained graph, something like this (if it looks very different from our main graph above, it might be because the number of trials/websites was too small):

If you'd like to run the full experiment, you can open reproduce.sh in a text editor, replace some-websites.txt with all-websites.txt, change runs to 25, and re-run the script.