15-440 Announcements

Mon, 10 Dec 2012 13:36:58 -0500

We will grade both 2A and 2B together at the final due date for the project. The overall due date has been extended by one day. If you did not pick up your midterm in class today, you can get it from the course administrative assistant, Kathy McNiff. Exam mean score 76.9%, stddev about 10%. (These are percentages - divide your score by 115).

Sample final for 2011 answers updated to fix bug in the security question answer

Mon, 10 Dec 2012 00:00:00 -0500

see subject

Sign up for final project review slots

Mon, 03 Dec 2012 00:00:00 -0500

Use the google cal to sign up for review slots for project 3. Please make sure to do so!

Sample finals and Midterm 2012 solutions posted

Thu, 29 Nov 2012 00:00:00 -0500

See the exams page

Bug fixed in presentation of Ricart and Agrawala DME Algorithm

Tue, 27 Nov 2012 00:00:00 -0500

JD Nir pointed out a bug in the pseudo-code describing Ricart & Agrawal's distributed mutual exclusion algorithm. The corrected version is in the class notes (txt, pdf).

Appointment slots for review going up

Tue, 27 Nov 2012 00:00:00 -0500

Within a few hours, you should be able to sign up for review slots for project 3. Please make sure to do so!

We are removing mapreduce framework from the suggested projects list

Fri, 16 Nov 2012 00:00:00 -0500

Unless you have already received an exemption from an instructor, please do not try to do a mapreduce framework project for p3.

Extra office hours (will be further updated)

Fri, 16 Nov 2012 00:00:00 -0500

dga will be holding office hours Monday 11am-noon. More entries will appear here soon, so check back. Timmy will be holding extra office hours on Sunday 3-6PM at the 3rd floor Gates common area.

dga extra office hours 11/16 11am-noon

Thu, 15 Nov 2012 00:00:00 -0500

see subject

Project 3 spec released

Fri, 09 Nov 2012 00:00:00 -0500

See writeup

Project 2 submission on autolab

Sun, 04 Nov 2012 00:00:00 -0400

Project 2 is now ready for submission on autolab. It runs the same tests as provided. As with project 1, please put everything in the contrib directory and submit a tar file with just the contrib directory. Make sure you do not include any binaries in there as there is a size limit on the submission. Lastly, don't forget to use the partners feature to indicate your partner.

Project 2 Part B tests released

Sat, 03 Nov 2012 00:00:00 -0400

Unit tests for storageimpl have just been released on AFS. You can run the tests via the scripts in the main directory (storagetest.sh, storagetest2.sh). Make sure GOPATH only has one directory in it (with your project). Note that the autolab tests may run with shorter lease durations (by changing the storageproto defines).

Project 2 stress tests released

Sat, 03 Nov 2012 00:00:00 -0400

Stress tests for project 2 have just been released on AFS. You can run the tests via the script in the main directory (stresstest.sh). Make sure GOPATH only has one directory in it (with your project). Note that the autolab tests may run with shorter lease durations (by changing the storageproto defines).

Weekend office hours for Project 2

Fri, 02 Nov 2012 00:00:00 -0400

We're holding some extra office hours this weekend to help you with Project 2. They're all going to be in the 3rd floor common area of Gates.
Timmy - Sat noon-3PM
Anthony - Sat 3-6PM
Alex - Sun noon-3PM
Bin - Sun 7-10PM

Prof. Bryant's office hours reduced today

Fri, 02 Nov 2012 00:00:00 -0400

Prof. Bryant will be available today, 11/2 from 3.00 to 3.30 in GHC 5113. If you have questions regarding Project 2, you'd be better off talking to one of the TAs. They will be holding office hours over the weekend (stay tuned for details).

Project 2 due date change

Thu, 01 Nov 2012 00:00:00 -0400

The due date for project 2 has been extended to Monday 11/5.

Mid-semester grades formula

Tue, 30 Oct 2012 00:00:00 -0400

(Quiz1/3 * 0.02 + Midterm/115 * 0.20 + (LSP+MAX(cracker,cracker official))/75*0.15)/0.37. Cutoffs 90% A, 80% B, 69.5% C, 59.5% D. This formula is NOT an exact representation of the contribution of these components to your final grade, but it should give you a good ballpark estimate of where you stand thus far. It does not include HW1.

dga office hours moved to Tuesday

Tue, 30 Oct 2012 00:00:00 -0400

dga will be holding office hours from 1-2pm today, NOT wednesday.

Project 2 Part A tests released

Fri, 26 Oct 2012 00:00:00 -0400

Unit tests for tribimpl and libstore have just been released on AFS. You can run the tests via the scripts in the main directory (tribtest.sh, libtest.sh, libtest2.sh). Make sure GOPATH only has one directory in it (with your project).

Office Hours today postponed.

Thu, 25 Oct 2012 00:00:00 -0400

Sorry folks, I need to cancel my office hours today. I apologize for any inconvenience, and will be available over the weekend.

Prof. Bryant cannot hold office hours 10/19 or 10/26

Thu, 18 Oct 2012 00:00:00 -0400

He will be out of town

Project 2 due dates and binaries updated

Wed, 17 Oct 2012 00:00:00 -0400

See assignments page for dates. Binaries and supplied libraries now support leases.

Homework 1 solutions online

Sun, 14 Oct 2012 00:00:00 -0400

See assignments page.

Quiz 2 graded on autolab

Fri, 12 Oct 2012 00:00:00 -0400

Quiz 2 has been graded and results can be viewed on autolab. It is out of 3 points. You get 1 point for passing each of the two test files, and this time we gave 1 point for handing something in.

Midterm debugging practice problems

Fri, 12 Oct 2012 00:00:00 -0400

Some debugging practice problems have just been added to the Exams page. These include solutions, but it is best to try to work through the problems yourself first. It is in your best interest to work through these as you might find similar problems on part of the midterm.

Midterm exam Tuesday 10/16

Thu, 11 Oct 2012 00:00:00 -0400

The midterm will be during class on Tuesday, 10/16. Coverage will be up through the lecture of Tuesday, 10/9. The exam will be closed book and notes. The best way to study is to review class notes, book readings, and work on problems from previous exams.

Project 2 posted

Tue, 09 Oct 2012 00:00:00 -0400

Project 2 has been posted on the assignments page. Please see the Piazza post for a little more information about this post of the project. There are a few changes coming soon, so begin carefully.

Sample midterms and finals are linked

Tue, 09 Oct 2012 00:00:00 -0400

Please see the exams page. Trust us - you want to study the practice exams.

Homework 1 handin extension

Tue, 09 Oct 2012 00:00:00 -0400

We will accept submissions for homework 1 up to 5pm today. You can submit either by email (staff-440@cs.cmu.edu) or physically at GHC 5113.

Clarification of Lamport's Distributed Mutual Exclusion Algorithm

Mon, 08 Oct 2012 00:00:00 -0400

The lecture notes for the class on 09/27 have been updated to provide a more careful presentation of the logic behind Lamport's Distributed Mutual Exclusion Algorithm. See page 10 of PDF.

Fixed non-critical error in HW1

Sat, 06 Oct 2012 00:00:00 -0400

HW1 p2 indicated the Lamport algorithm but described Ricart and Agrawala. Changed to describe Lamport. The answer to this question is unchanged.

Homework 1 out, due 10/9

Tue, 02 Oct 2012 00:00:00 -0400

See the assignments page.

Project 1 Part 2 - Password cracker Handin

Sun, 30 Sep 2012 00:00:00 -0400

See the Project 1 FAQ for instructions on how to handin part 2.

Updated version of stest

Thu, 27 Sep 2012 00:00:00 -0400

Fixed a logging bug that caused it to record only the results of the first test

Source code for LSP implementation made available.

Thu, 27 Sep 2012 00:00:00 -0400

The most recent code distribution for Project 1 includes source code for our implementation of LSP. This means 1) you can compile & use this code so that you can run your Part B code on top of our version of LSP, and 2) you can study & examine this code to see what a working implementation looks like. If you're trying to fix up your LSP code to get the extra 10 points for the assignment, you can let our code guide you, but of course, you cannot just copy it.

Bug fixed in lspnet code

Wed, 26 Sep 2012 00:00:00 -0400

Turns out the implementation of ReadFromUDP did not handle the dropping of packets properly. Fortunately, this capability has not been used in any of our testing code.

More helpful hints added to FAQ

Tue, 25 Sep 2012 00:00:00 -0400

See the Project 1 FAQ for new hints on the risks of race conditions, and how to avoid them.

Helpful hints added to FAQ

Mon, 24 Sep 2012 00:00:00 -0400

See the Project 1 FAQ for new hints on tracking down bugs that cause the program to hang, adding your own packages, and handling the different flavors of close operations.

Updated testing code

Mon, 24 Sep 2012 00:00:00 -0400

A race condition in the test file lsp12_s_test.go has been fixed. It also does better error checking.

Project 1 Part 1 - LSP Handin

Sun, 23 Sep 2012 00:00:00 -0400

See the Project 1 FAQ for instructions on how to handin part 1.

Project 1 Logistics

Sat, 22 Sep 2012 00:00:00 -0400

Here's some important information regarding Project 1.

We will NOT be extending the deadline(s) for this project. The deadlines are Monday 9/24 (Part A), and Monday 10/1 (Part B).
You will hand in your programs via autolab. Instructions are forthcoming.
In terms of late days, Parts A & B will be treated as if they were separate hand ins.
See the Project 1 FAQ for more information about how we will compute grades for the project

Corrections to reference implementation of LSP client & server

Sat, 22 Sep 2012 00:00:00 -0400

Turns out we were not handling the epoch events properly (see pp.5-6 of the project description). This has now been fixed. Compiled versions of echo client and server are also updated.

Improvements to project description.

Sat, 22 Sep 2012 00:00:00 -0400

Clarified the handling of epoch events (pp 5-6) and the three different gorotines in a suggested implementation (p. 13).

Bug fix in testing code.

Sat, 22 Sep 2012 00:00:00 -0400

Corrected an error in file lsp12_s_test.go that could cause the failure of one test to make the next test also fail.

Project 1 Weekend Office Hours

Fri, 21 Sep 2012 00:00:00 -0400

We will be holding additional office hours this weekend to help with Project 1. Professor Bryant will be available from 2:30-3:30 Saturday, 9/22 in the 3rd floor cafe area of Gates. Timmy will continue at 3:30 Saturday 9/22 in the 3rd floor cafe area of Gates. Alex and Anthony will be holding office hours 12-5 Sunday, 9/23 in Gates 5205. Bin will have office hours 7pm-10pm Sunday, 9/23 in the 3rd floor cafe area (originally planned in Gates 9003).

Specification changes for close operations in LSP

Thu, 20 Sep 2012 00:00:00 -0400

We have made some small changes to specifications related to the different LSP client and server close operations, regarding the possible orderings of method calls, and what the effect of a call to CloseConn should be. These are documented in writeup.pdf (pp. 9-10), and the Project 1 FAQ

Extra office hours this Friday

Wed, 19 Sep 2012 00:00:00 -0400

I will be holding extra office hours this Friday at 3:30pm for help with P1. Note that you can still get P1 help at regularly scheduled office hours. Please try to think about and work through the issues beforehand as that's good experience. If you haven't thought about and worked on the project much, you'd better start real soon as these projects cannot be procrastinated and two weeks have already passed. You can find me at GHC 7010.

More suggestions in writeup for P1

Tue, 18 Sep 2012 00:00:00 -0400

The writeup for project P1 has been updated to give bit more information for how you might want to structure your LSP server and client code. See p. 13 of writeup.pdf.

Micro Quiz 2 handin

Mon, 17 Sep 2012 00:00:00 -0400

As announced on Piazza, micro quiz 2 can be handed in through Autolab. There is no autograding for this assignment, so results will be posted after the deadline. Please let me know if there are any issues with handing in the assignment. Waitlist students do not have an autolab account yet and will need to email me (timothyz at cs dot cmu dot edu) to create an account.

Improvements to Q2 testing code

Sat, 15 Sep 2012 00:00:00 -0400

We've increased the lengths of the timeouts, and put new deadlock detection logic in cvar_rightleft_test.go. These should make the tests more reliable.

Change to specification for Project 1, Part A

Fri, 14 Sep 2012 00:00:00 -0400

Turns out we made a bad design decision in the specification of the LSP Server. We are changing the specification for the CloseConn method so that it should return immediately. See the discussion in the Project 1 FAQ. Affected files include the writeup, the reference implementation of the LSP package (lsp12.a), and the official version of the server.

Extra office hours this Saturday

Fri, 14 Sep 2012 00:00:00 -0400

Multiple students have requested some extra help so I will be holding extra office hours just this Saturday from 11:00 to noon. You can find me at GHC 7010. Email me at timothyz AT cs DOT cmu DOT edu if you cannot get into the building.

Additional test added to Q2 code

Fri, 14 Sep 2012 00:00:00 -0400

We've added another set of tests to the Q2 code distribution. It's called "cvar_rightleft_test.go". It specifically targets the need for Wait to atomically release the mutex and suspend the thread. Give it a try, 'cuz we'll be running it on your code.

Help on Project 1 tonight 7-8pm in GHC 5205.

Thu, 13 Sep 2012 00:00:00 -0400

Some of the TAs will be available tonight in this cluster to help students with project 1. Whether you are just getting started, or you have specific implementation issues, this would be a good chance to make progress on the assignment.

Micro quiz 2 available

Thu, 13 Sep 2012 00:00:00 -0400

See the assignments web page. Due Monday, 9/17, before 10:00 pm.

Micro quiz 1 solutions posted to Piazza

Mon, 10 Sep 2012 00:00:00 -0400

Please login to the Piazza site to review!

Additional method in lspnet.go, and updated lsp12 packages

Mon, 10 Sep 2012 00:00:00 -0400

We've added the Close method to the proxied version of UPDConn. You should call this function as part of your implementation of LSP for the client (Close) and the server (CloseAll.) The official versions of the LSP package lsp12.a have been updated accordingly.

Additional test added for Part A of assignment

Fri, 07 Sep 2012 00:00:00 -0400

There is a new file /go/src/P1-f12/official/lsp12/lsp12_s_test.go in the code distribution to provide more systematic testing of your LSP code. It is included in the version of P1-f12.tgz in /afs/cs.cmu.edu/academic/class/15440-f12/P1. You will also see in this directory a file updated-files.txt and a copy of the complete go code distribution.

Project 1 available

Wed, 05 Sep 2012 00:00:00 -0400

See the assignments web page.

Micro-quiz 1 availabile

Wed, 05 Sep 2012 00:00:00 -0400

See the assignments web page. Due Friday, 9/7, before midnight.

Course placeholder, but go learn Go

Wed, 01 Aug 2012 00:00:00 -0400

To get ready for fall, go take A Tour of Go, the programming language that will be used for the assignments.