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There where three student at today's re-exam - all passed.

If you want to know your grade, send me e-mail using your uio mail account and I will e-mail your grade to you.

-- Eric

I am experiencing problems with Zoom!

Please wait ...

And while you are waiting send me your mobile phone number so that I can reach you if need be!

-- Eric

The August re-exam will be tomorrow starting at 09:30 - see the link below. Note, that we use a waiting room feature of Zoom and so you will have to wait to be admitted. PLEASE use your uio login to uio.zoom.us.

You will be asked to show your student ID at the start of the exam. (If you lost your card, use your passport.)

Three students have signed up.

There is 30 minutes in total per student.

The exam is an oral exam: I will ask you to explain several vital parts of the curriculum.

IF you have problems connecting, send me mail. If it is close to the time you are to show up, send me an SMS at +4540251650!

You are welcome to check out the exam link NOW. You can enter the waiting room and leave as often as you want :-)

Good luck :-)

Sincerely Eric

Eric Jul is inviting you to a scheduled Zoom meeting.

Topic: Konteeksamen IN...

Three students are signed up for a delayed exam.

The date and time has not, as yet, been set, but it WILL be an ORAL EXAM.

-- Eric

There has been some technical problems with the new systems for grading the exam.

I do hope that the problems are gone now and that the grades will show up in studentweb by tomorrow. They DO need to make their way from Inspera to the central exam system...

The grades are done, here is the distribution for IN4330:

Question 20:

Hei, i oppgave 2.2 skal vi lage et test-program til barrieren vår. Jeg sliter litt med å skjønne hva vi skal lage her. Skal vi lage et testprogram som tester funksjonaliteten i klassisk test-program-stil, eller skal vi lage et use-case som beviser at barrieren vår funker? (For eksempel en array-sort eller liknende)

Answer:

You figure it out.

-- Eric

Question 19:

Er det meningen at vi skal skrive et program med all funksjonaliteten til en cyclicbarrier (reset, isBroken o. l.) eller bare hovedfunksjonaliteten?

Answer:

You figure it out - perhaps by reading ALL the previous questions and answers...

Question 18:

In Question 2.1, are we allowed to use the methods wait(), notify() and notifyAll(), which are implemented in the java Object class? Or are we supposed to create a solution without using these methods?

Answer:

Exam question 2 says "... Semaphores" - so a solution without semaphores seems to miss the point...

-- Eric

Question 17:

Hei! Jeg lurte på om den parallelle mergesort algoritmen vår, må fungere for ett vilkårlig antall tråder. Eller om det er godt nok at den fungerer for like mange tråder som vi har kjerner på maskinen vår.

Answer:

You figure it out.

-- Eric

Question 16:

I oppgave 3 står det at hele løsning på gjøres rekursivt. Betyr dette at trådene selv må dele opp data, eller kan vi dele opp data for så å la hver tråd jobbe rekursivt?

Answer:

You figure it out.

-- Eric

Question 15:

When you are asking for a speedup and output for question 3.2, is this supposed to be for the test array {120,1,101,503,57,158,451} that is provided in the example? Or can we create larger arrays for this? And should we provide the speedup or does it suffice to give this in task 3.3?

Answer:

You figure it out.

Consider WHY it says " ... 10 million integers." in the exam text.

-- Eric

Question 14:

På oppgave 2, er det ment at man skal kunne bruke SemCyclicBarrier akkurat slik man ville brukt CyclicBarrier?

Eric's translation: Shall SemCyclicBarrier be used just like CyclicBarrier?

Answer:

You figure it out (see also previous related questions).

-- Eric

Question 13:

Skal vi bruke semaphore fra java biblioteket, eller skal vi implementere det som nevnt i forelesning?

Eric's trranslation: Can we use Java's Sempahore class?

Answer:

Yes

-- Eric

Question 12:

Det står i oppgaven "Submit the program and its output.". Skal vi skrive output til en txt fil? Hva skal output være?

Eric's translation: Must we provide input in a .txt file? What shall it be?

Answer:

You decide.

-- Eric

Question 11:

Går det greit om vi leverer enkelte spørsmål på norsk og resten engelsk?

Eric's translation: Can we mix languages?

Answer:

Ja, that is greit!

Yes, det er fine!

-- Eric

Question 10:

Er grafer over speedup og bilder som forklarer paralelliseringen noe vi burde unngå?

Eric's translation: Are we to avoid graphs of speedup and pictures that explain the parallelization?

Answer:

Nei! Tag dem GJERNE med!

No! You are welcome to include these, if you desire.

Question 9:

Question related to task 3, merge sort.

Do we have to use the sketch? I wrote my own sequential merge sort with optimizations, I include these optimizations in the parallel variant so that the comparison is fair. Is this okay? or do we have to use the sketch?

Answer:

No, you do not need to use the sketch, but remember that the exam text reads: "Describe the design of a
solution that MUST be loyal to the algorithm, e.g., it must still be
recursive."

-- Eric

Questions concerning the FInal Exam while it is in progress, should be submitted using the instructions in the Exam on Inspera.

I have answered eight questions so far.

I will answer more questions tomorrow mid-morning.

-- Eric

Question 8:

Question 1.2 is titled "Caching", but the question itself does not ask anything about caching. Is it expected that we include an explanation of caching in our answer? I find this hard to do properly in 100 words.

Answer:

You are to figure this one out yourself - it is part of the exam to do so. And to find a good answer to the question based on what you have learned in the course.

-- Eric

Question 7:

Hello! In Question 3.2 it says "Submit the program and its output" and in the next question (Question 3.3) it also asks us to create a test program. Are we supposed to create two separate test programs for Questions 3.2 and 3.3?

Answer:

Submit two programs, one for each question. The one for question 3.3 can include the program from 3.2.

-- Eric

Question 6:

Hvordan skal vi levere programmene vi lager? Er det greit å laste opp en zip-fil, evnt. *.java filer?

Eric translation; How to upload submission? Is a zip file OK?

Answer:

Det er greit med EN zip fil med alle dine .java filer og .pdf og .txt og ...

It is fine with a zip file containing all your stuff.

-- Eric

Question 5:

Answer:

You have to use Semaphores - it says in the title.

Cyclic buffer is the same as cyclic barrier in this case (even repeated proof-reading didn't catch this error!)

-- Eric

Question 4:

Related to 3 (merge sort)

Are we allowed to use RecursiveTask along side with ForkJoin to solve the merge sort task? It seems sort of like cheating, since the library (standard in java 8) performs a lot of the load balancing for you.

Answer:

Yes, but you will have to:

1. Figure out how to use it
2. Justify using it
3. Get good speedup

-- Eric

Question 3: (open to see entire answer)

I'm working on the IN3030 exam and I'm working on the merge-sort parallelization. I have a working solution (with a great speedup!) that works very well up until about 80 million integers. When I increase the size past this, I get a java.lang.OutOfMemoryError exception, which I think happens because there are a lot of recursive calls with large arrays in them at the same time. I was wondering if this is something that would make me lose points on the exam, when the exam says that we have to sort at least 10 million integers.

Answer:
Is 80 million < 10 million??

I must be getting old... ;-)

If you meant 8 million, well, do not worry - just run it with as many int that you can - preferably after following the instructions below.

If you get an java.l...

Question:

I am currently taking the IN3030 exam for this year.

I do not understand if you want us to submit the code and PDF separately.

As an example question 3.2  says "Submit the program and it's output.", but we 

are only able to submit a single PDF file.

I just wanted to make sure i am doing the right thing by adding everything to a PDF.

Answer: Upload a single file - preferably a ziped directory with all that you want to submit. If this is a problem print all files that you want to submit as a single PDF file and submit it.

-- Eric