0 votes 0 votes how to approcach such questions please help with all the three statements. CO and Architecture made-easy-test-series co-and-architecture cache-memory + – Markzuck asked Dec 21, 2018 edited Mar 3, 2019 by akash.dinkar12 Markzuck 666 views answer comment Share Follow See all 15 Comments See all 15 15 Comments reply OneZero commented Dec 21, 2018 reply Follow Share shouldn't doubling the associativity increase the tag bit by 1? 0 votes 0 votes Shaik Masthan commented Dec 21, 2018 reply Follow Share @Markzuck Type the question instead of screenshot.... please edit your question. Coming to the question, no.of tags = no.of lines in the cache. Associativity effects the number of tag bits but not number of tags S1 always true, s2 always false, s3 always true 1 votes 1 votes Markzuck commented Dec 21, 2018 reply Follow Share Sorry for the screenshot. But ans given is b? How can number of tags change without change in no of tag bits? 0 votes 0 votes Shaik Masthan commented Dec 21, 2018 reply Follow Share But ans given is b? Do you think answers provided by them are always correct ? How can number of tags change without change in no of tag bits? Doesn't get what you are saying, read one more time my previous comment Sorry for the screenshot atleast edit it now. 0 votes 0 votes Magma commented Dec 21, 2018 reply Follow Share S1 always true, s2 always false, s3 always true given answer is right 0 votes 0 votes Magma commented Dec 21, 2018 reply Follow Share today one more student post the same questions and I write the answer in very well manner at the time I save my answer he is just lock the question and my answer was remove :3 I tell him to unlock it so that I can auto-load my content but he didn't do that -_- 0 votes 0 votes Shaik Masthan commented Dec 21, 2018 reply Follow Share @Magma which answer is right ? either mine or made easy ? note that madeeasy provide s2 and s3 are true but i am saying s1 and s3 are true. 0 votes 0 votes Magma commented Dec 21, 2018 reply Follow Share made easy answer is right 0 votes 0 votes Shaik Masthan commented Dec 21, 2018 i edited by Shaik Masthan Dec 21, 2018 reply Follow Share @Magma can you explain ? before that just read my comment 0 votes 0 votes Magma commented Dec 21, 2018 reply Follow Share S1 : Direct mapping : TAG LINE NUM BO dOUBLING the line size ---- > Block offset is decrease by /2 In direct mapping we know that no of lines * block offset = cache size therefore , even if you increase the line size , the block offset will decrease by same , SO overall cache size remains const therefore , TAG bits is const SET - ASSOCIATIVE MAPPING : TAG SET NUM BO DOUBLING the line size -----> NUMBER OF SETS INCREASE BY X 2 ----> NUMBER OF BLOCKS ARE DEDUCE BY 2 ----> BO IS DECREASE BY /2 so ,if we increase 1 bit from line number ----> it will decrease 1 bit from the BO therefore , In any cache organization you observe that (sets * block size = const) as long as you put this "k" as const where k is k-way set associativity therefore , no of tags remain const in set-associtive mapping tag block off doubling line size ---- > number of blocks deduce ----> block offset also deduce therefore TAG bit is increase here therefore we conclude that by doubling the line size implies higher tag bits S1 is false always s2 : Doubling the associativity doubles the number of tags in the cache TAG SET NUM BO doubling the associativity means set number decreases and here block size is fixed (given ) therefore it doubles the number of tags in the cache S2 is right always 2 votes 2 votes Shaik Masthan commented Dec 21, 2018 reply Follow Share we have to fix the cache size, right ? 0 votes 0 votes Magma commented Dec 21, 2018 reply Follow Share yess 1 votes 1 votes Shaik Masthan commented Dec 21, 2018 reply Follow Share @Magma it is asking about no.of tags but not number of tag bits, i already mentioned in my comment 2 votes 2 votes Magma commented Dec 21, 2018 reply Follow Share I did bad mistakes always :3 0 votes 0 votes Himanshu Kumar Gupta commented Aug 20, 2020 reply Follow Share If question are asking in context of number of bit then giver answer is right but if question are asking in context of number of tags (== number of lines) then @Shaik Masthan sir answer is right.. 0 votes 0 votes Please log in or register to add a comment.