Preparation strategy

Question

After doing a lot of numerical and understanding the concepts well I am not be able to find out the accurate answer within a certain amount of time plz suggest me something what should i do  ?

Comments

“doing a lot of numerical”

From which source did you do? And did you solve them on own or referred the solution?

“and understanding the concepts well”

Which topic have you understood well?

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I do the numericals from gateoverflow site and from unacademy platform
I understood DMA I/O Pipeline and Cache  concepts  well
I learn this concept from vishwadeep gothi sir from YouTube platform
I used to do half of the solution step right but not be able to takeout the accurate answer I first i try to solve by own after 15 -20 mins i go for solutions

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Since you have understood cache portion well can you give a scenario (cache structure and access sequence of block addresses) which can cause a conflict miss?

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The program and data place in small fast memory to reduce the memory access time thus reducing the total execution time of progrm such fast small memory is called cache Memory. It is temporary and it placed between the Cpu and main memory Basically the content of main memory are stored in short form in cache for the use of Cpu. If some of portion of Cpu is not found in cache then it goes to main memory and this suitation is called a Cache Miss and if the content that cpu demand is found in cache then it is called as Cache Hit

Conflict Miss is also called as collision miss while the block replacement if the some blocks occurs at same set or same place then the conflict miss occur. It is occur in Direct Mapping and Set Asscociative Mapping
But Not in Fully Associate Mapping

Access sequence of the address are:-
The CPU generate the address of main memory to find a particular data
 1)Direct Mapping :- In directmapping

 tag | line | Block  

so first we will se the line ie also called cache block no.  Then we find for Tag bit and then we used goto find for block no.  Supose 3 blocks is given 000 001 011 so which block we want

Line no =Main memory % no of blocks in cache

Memory block no= Byte address / Block size

Tag = Main memory address - log2(cm block + block)

2) Set Associate Mapping

Tag| set no. |Block no

First we find we have to find the set no.  Then tag field then Block no.

No of index = No. Of block in cache/ Associativity

3) Fully Associative Mapping

Tag| Block  

 first we go for tag  then we find block to get memory address

No. Of comparator=No of block in cache

Size of comparator = Tag bit

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This is not University exam :) I just asked a sequence of addresses which can cause a conflict miss – for simplicity you can assume a cache of size 32 KB, 64B block size and direct mapped.

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Okkk sir so according to you what should i do Now should i continue to keep solving numerical or else focus on my concepts only 8 months is remaining and i feel so depressed what to do what not to Please sir suggest to what should i do ??

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You mean you cannot answer this? A question on conflict miss was asked a couple of years back and only about 50/100000 aspirants gave the correct answer. But almost 90% of top 1000 rankers gave the "expected wrong answer". I was expecting at least that since you told you have understood cache concepts well.

"suggest what should I do"

From what you have told the only thing I can say is your current method of study cannot get you to within a top 1000 rank. Just reading your answer one more I think you are by-hearting some notes.

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Sir  I keep on revising my notes so many of the concept become learned by heart

What i used to do i ex.:- coa first i solve the numerical then if i am not be able to solve that then i refer my notes and gateoverflow site reference and aftert that i  revise my notes throughly so that why the become learned by heart I made a habit of revising notes after completing every iteration of numerical solving But i think this approach is wrong because  i am not ne able to gave a single answer of your questions

So sir what method should i follow to improve my problem-solving skills and understanding the concepts in more depth should i read the standard book again

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Whatever be the resource, you should have an objective while using them. I gave you a question but even without me giving it, you should have such questions in mind while studying topics. In that case you'll naturally filter out most notes unless you're already familiar with those topics. For my question you haven't even given a wrong answer -- you should try to do it following a standard book. If you don't have an objective even reading standard books serve no purpose.

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Sir same i was facing a lot of difficulty i just try to mugged up the concepts instead of understanding the accuracy behind that concept in the real world

As i am doing self study so i don't understand from where should i find this

I also want to know the reason behind that whats the problem behind that how that a particular thing is used for that how should the solution fix for that i have to know about each and every concept

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If you are serious about GATE you should now press the Reset button. Your current method might work for PSU exams where very less new questions come, provided you have good memory power and speed but not for GATE.

I think you are not able to answer my question probably because you're not understanding the question itself. I suggest to first cover the basic subjects - discrete mathematics, algorithms, data structures etc and then come here. The thing is if you can do well in one subject you can do well in almost all.

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Okk sir As u say i will complete that subjects first then i'll move towards other subject and I am serious aspirant of gate and i will start from basic subject from now onwards

But i understand your question sir u asked me the that conflict wala question and u expect that answer in the form of objective manner and i gave u answer in subjective manner which completely not reliable
Because at the end of the gate is a objective test

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Which year did India get independence? 

Answer is “1947” irrespective of the examination type. But if such a question come in University exam I guess most of you will write like 

India is a great nation. So many freedom fighters fought for our independence. blah blah. blah blah. Quit India movement happened in 1942…. Mahatma Gandhi was assassinated in 1948.

What you did is the same – but at least somewhere in between you should mention “India got independence in 1947”. 

Irrespective of the exam type (subjective or objective) your answer to my question should get “0” mark (in most good colleges like IIT it would be the case). But in most of the Universities in India you might get some or even full mark for it – take it as a blessing or curse. Also in good universities if you write “1947” as answer you’ll get full mark and if you write unwanted stuffs like I did here, mark will go down – that’s why they are “good” universities.

And even now, you have not understood my question – you understood only the keyword in it similar to “independence”.

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Absolutely yes sir. I understand the difference between universities exam and gate exam

I think I'm not getting your question so can you plz explain me about your question and guide me something about my preparation as i need start from scratch Now

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can you give a scenario (cache structure and access sequence of block addresses) which can cause a conflict miss?

Cache size: 32 KB, block size: 64 B, direct mapped.

Answer should be like

a, b, c, d, a, c, b, ...

where a, b, c, d… are block addresses and the sequence should be causing a conflict miss. 

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Okk sir Now i got it

 From now afterwards  i'll understand the question before giving the answer

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Your current method might work for PSU exams where no new questions come, provided you have good memory power and speed but not for GATE.

What about this question: https://csedoubts.gateoverflow.in/26839/nielit-nic-scientist-b-2020-set-c-ques-75

Could you please tell me whether this is a new question or old and if it is old question then can you tell me the source from where it is copied ? 

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I dont know - but it should be copied from some book :) Thats why some of the questions are tough to answer within the exam time unless you have solved that question before.

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@Arjun sir, it should be or it should not be. We don't know :)

We always have to talk with facts and reasoning. This is just an example and there can be other questions too and it might present a negative image of something. You  tell this to other and it will be spread that no new questions come in psu exams without having any proof of this.

I am telling you one incident which is similar to this:

Few years back when I joined ISI, I was talking to a girl who is from IISc mtech research course to whom I have talked till one year (you must know her but I am not disclosing her name), There was a discussion 
going on institutes. Since, in my batch, around 1/3rd people were from iits, some were from nits and isi. so I told her and said no person is from iisc, so she said, no one will go from iisc to isi, then I have provided various proofs of people who went from IISc to ISI and after this, she did not have any word to say. I have said anyone can go from any institute to any other institute for a particular interest.
I have also said if you don't know about any institute and its history then please don't make any negative comment about any institute.
Later, She blocked me and next year one person from iisc joined isi mtech course.

So, Saying something correct might or might not hurt someone but if you say something wrong or spread negative things which you actually don't know about someone or something and probably someone has not done it, then it hurts more :)

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Well the point here is if PSU exams include "new questions" like GATE, ISI etc. We do have all the previous year NIELIT, ISRO questions here itself. Most of them search hit to previous year GATE questions and to a book which I believe is Timothy Williams. And the reason is obvious - GATE questions are framed by IIT professors, do PSUs spend effort in doing this? I don't think at least for CSE, that's the case as seen from previous year exams. Recently they are changing the options at least. But NIELIT aptitude questions are of good standard and probably not copied. My comment is mostly for CSE questions -- I'm not sure for other branches too.

So, I stand with what I said but "no new questions" might not be true. So, I have changed that to "very few new questions ".

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Well the point here is if PSU exams include "new questions" like GATE, ISI etc.

If you think that GATE includes “new questions” then please check here:

https://gateoverflow.in/333192/Gate-cse-2020-question-39

and  https://gateoverflow.in/?qa=blob&qa_blobid=10691577044077116257  (From Kenneth H. Rosen, already mentioned in the comment section of selected answer)

Make left to right and right to left and change A to W and new question is prepared.

This is almost 2 years old gate question and not very old gate question. Since, you were talking about effort taken by PSUs to make new question then could you please tell me, How much effort would be taken by committee of IITs and IISc professors to make this "new" question. Since, you were talking about copied from book, I could also say that they make some questions like this because there are many good books for a subject and even there are very very good books for a particular topic and it involves exercise questions. But I won't say that because I have not made any research about every question.

If there is problem in one side then other side is also having problem.

Gate is more popular than ISI entrance exam and committee of IITs and IISc professors who are highly qualified have to make 65 quality questions in a sufficient amount of time but I will never expect a 2/1 mark(s) question like above which can be prepared one day before the exam. I would like if some questions come with ambiguity/errors because they have made by their own, so if some error would come, it will not be an issue for me but I will like the effort they put in to make new questions.
 
Requirement and Purpose of both PSUs and GATE are different. Gate is conducted for master's degrees where students have to go through various subjects in which they might have to face various research problems which might not be easy and so, I think they need students like that who can solve questions like that which will help if they go for further education like PhD, post-doc, ra and even industry if they join good team in a company etc and I think that's why they ask mostly new questions (which I am believing) (they were expecting from students to think in exam) and many PSUs recruit people for various posts and according to their post, salary etc, their exams have easy/copied questions from gate/new/difficult questions. They might need people with good aptitude and basic knowledge of computer science. They might not need research-oriented people.
I don't know whether they face any research problem or not. I also don't know if we assume that all cs related questions are copied then is it possible for someone to see all the resources from where question can come, to solve the problem. I don't think, we can say them to ask gate questions. It's their decision
according to their requirements based on the things which I have mentioned above. It is like two companies x and y are coming for campus recruitment. x is having tough questions and y is having easy and copied questions. We, generally, don't say to company y, please ask tough questions because company y has different recruitment process and company x has different recruitment process according to their requirements.

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🙄 Are you really comparing GATE and PSU questions?

First of all there is a difference between quality question and “copied” question. Like you told PSUs have no need to ask newly framed questions but at the same time they should not CTRL+C. CTRL+V the questions from somewhere (mostly previous year books) because that gives an unfair advantage to those who byhearts them. Thats the main point I was stressing.

I’m not part of GATE committee and I have no reason to favor them. But the number of copied questions even in GATE CSE should be in single digits (negligible) but concept wise 80 or 90% are the same every year. But if we consider PSUs more than 25% are usually copied from previous year GATE book only. Nowadays we are not merging duplicate questions of PSU’s but you can see this page for example: https://gateoverflow.in/tag/isro2016?start=60

Question title shows from where the question is taken exactly the same with no change in options and not even shuffling.

This is the latest NIELIT exam and you can check and see how many are exactly the same GATE question. In GATE, one gets 3 minutes to solve a question whereas in NIELIT exam I guess it is just 1 minute. So, they are encouraging “by-hearting”. And I’ll be curious to know if “by-hearting” has any use in PSUs.

https://gateoverflow.in/tag/nielit2022jan-scientistb

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Also I challenge all ISI people (or any institute people) to make answer key for the next ISRO exam and make it at least 90% accurate. I don’t think anyone can do this because easily 10% will be wrong even after they correct their keys (mostly they copy the answer keys too from somewhere and even make mistake in copying). For GATE CSE over the last 5+ years GO have been making answer keys 95-100% accurate. I think we made it once for ISRO but never bothered again.

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Are you really comparing GATE and PSU questions?

I am not comparing anything, Why would I compare ? I have no relation with any of the two. I was answering your question and making your statements correct so that wrong/incomplete info should not be spread.

I have seen on many places, some influential people write something and people start believing them that they are correct without doing any research about it and start making a negative image of something/someone.

This is not a personal attack on you or any educational institute or anyone. First you said "no new questions come in psu", so I corrected your statement by giving an example. Next, you said "...”new questions” like GATE/ISI etc.", so, I had given a counter-example. Those things we don't know, we should simply say, we don't know. We don't know whether only single digit(negligible) number of copied questions come in gate or more than that.
I have shown one example. Other examples can also be possible. We don't know. 
As I said there are many books and resources are available, it is difficult to get the answer of this question, you are guessing it which can or can not be true. 
Those person who set the paper can tell the exact number.

We can only say, most of the times, gate questions do not repeat. 

 Like you told PSUs have no need to ask newly framed questions

I have never said this, probably you should have to read that comment again :) 

Both have goods and bads and I think, they should have to work on it. I know what you want to convey the message about PSUs and I agree on some part of it. My intention was to make things correct.

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This discussion is going no where. These are the points I wanted to convey

1. No new questions come in PSU exams – hard to prove but typically 25% questions are exact same as previous year GATE and some are taken from question banks. Previously previous year questions used to be exactly the same including for option ordering – recently at least the options are getting shuffled or changed a bit.Considering all these, I’ll correct my sentence as “most questions are repeated in PSU exams”
2. Speed and practice are important for PSU exams – since many questions are repeated and time per question is far less compared to GATE, those who practice all previous year questions and remembers the answers have an edge for PSUs. For GATE also practice is important but no need to remember the answers and time per question is more during the exam.

Feel free to correct or add more points :)

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This discussion is going no where.

It is the above discussion so that you have made your statements correct :) It is the game of words which can or can not hurt someone. You should have to mention both sides of GATE and PSUs or anything you would like to mention. It should not be one sided and should not give feel like biasing. If a person who made some questions by his own for some PSU exam would not be happy if he/she knows what you have written initially.
    
I have nothing to say now. I have already said what I wanted to say regarding your statements. It's upto you whether you can understand the things which I have written above or ignore them :) 

 A question on conflict miss was asked a couple of years back and only about 50/100000 aspirants gave the correct answer. But almost 90% of top 1000 rankers gave the "expected wrong answer".

I was thinking to make comment on this 50/100000 and 90% of top 1000... but phir socha rehne dete hain waise bhi @Arjun sir ko itna pareshaan kar diya hai (then thought of leaving it as I have already bothered arjun sir so much) :P and @Vaishnavi Gadhe got tired also after clicking on notification button everyday and found nothing useful.

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Thank you for correcting me.

If a person who made some questions by his own for some PSU exam would not be happy if he/she knows what you have written initially.

I'll be very happy to meet him/her 😀 But moreover Im interested to know if such people are encouraged in PSUs or if they have any plan to do so. 

I was thinking to make comment on this 50/100000 and 90% of top 1000

Do you want proof for this? This 50 is exact figure from Pragy's app and we had most of the toppers there. But you can argue that even the last ranker in GATE might have got this correct and he may not have used Pragy's app 😇