CS 2012: Set A, Question 0

To discuss a Question: Post "Pattern ID, Question Number", so that the students can understand your question

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Total votes : 48

Re: CS 2012: Set A, Question 0

Postby Priyankadevesh » Mon Feb 13, 2012 5:16 pm

Yup...it wil b O(n^2logn)
@sameer2009
hav u attemptd the tag directory question.it shud b 40kbits.wat urs
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Re: CS 2012: Set A, Question 0

Postby Priyankadevesh » Mon Feb 13, 2012 5:41 pm

0810310401 wrote:
Priyankadevesh wrote:It shud be 40kbits for tag directory.cache tag directory wil maintain tag info for each se not for each block.and its about directory means how much tag info wil take,as for each block within a set,tag bits wil b same.
Means 4 block wil have same tag bits so we have to insert only 1 value for each 4 block in directory.wat u say


then how will u confine that any cache block contain valid data and then if any block is to be replaced from the cache to disk then if replacement bit is not for every block then u have to write every block to disk.

from the given virtual address it cud b find which set a block belongs. from 0 to 4 bit wil contribute to decision of offset within a block.
set bits are from 5 to 15 bits
,rest from 16 to 31 wil decide tag bits.so conclusion is we hav to decide only set not block.
Answer to ur question
to transfer a block between cache and main ,if block address is given we can decide the set to which that block belongs.so there is no need to store tag info for each block,as we can deduce the set info and tag info changes at the set level nt at block level.so tag directory=2^11*20->40kbits
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Re: CS 2012: Set A, Question 0

Postby t4tarGATE » Mon Feb 13, 2012 5:44 pm

Priyankadevesh wrote:@t4targate
can u explain why A in IP address distribution.m quite sure about it .it must b B.

preventing ambiguity for distant n/w
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Re: CS 2012: Set A, Question 0

Postby t4tarGATE » Mon Feb 13, 2012 5:46 pm

targate2012 wrote:
Priyankadevesh wrote:@t4targate
can u explain why A in IP address distribution.m quite sure about it .it must b B.


Even I have this doubt, what is the logic behind choosing (a) over (b) ? Can anyone please explain ?
Is it because there will be duplicate IP addresses between org A and B ? But in that case, the subnets are different.

yup...u r right...there is no problem within subnet but it creates problem for distant router...take some values for better understanding
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Re: CS 2012: Set A, Question 0

Postby t4tarGATE » Mon Feb 13, 2012 5:50 pm

Priyankadevesh wrote:
0810310401 wrote:
Priyankadevesh wrote:It shud be 40kbits for tag directory.cache tag directory wil maintain tag info for each se not for each block.and its about directory means how much tag info wil take,as for each block within a set,tag bits wil b same.
Means 4 block wil have same tag bits so we have to insert only 1 value for each 4 block in directory.wat u say


then how will u confine that any cache block contain valid data and then if any block is to be replaced from the cache to disk then if replacement bit is not for every block then u have to write every block to disk.

from the given virtual address it cud b find which set a block belongs. from 0 to 4 bit wil contribute to decision of offset within a block.
set bits are from 5 to 15 bits
,rest from 16 to 31 wil decide tag bits.so conclusion is we hav to decide only set not block.
Answer to ur question
to transfer a block between cache and main ,if block address is given we can decide the set to which that block belongs.so there is no need to store tag info for each block,as we can deduce the set info and tag info changes at the set level nt at block level.so tag directory=2^11*20->40kbits

answer would be 16 and 160k.... no of tags = no of lines but not no of set.... set only effect the size of tag but not no of tags...so total no of tags = no. of lines=2^13... so total size for tags=(16+2+1+1)x 2^13=160kbits..
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Re: CS 2012: Set A, Question 0

Postby Priyankadevesh » Mon Feb 13, 2012 6:08 pm

@t4targate
i agree that tag info is for each line but in set associative cache tag info is same for each line within a set and
question is abt tag directory means how many tag entries wil b in tag directory.at direct mapped cache tag info changes at line level so in tag directory of direct mapped cache tag info is present for each line,but in case of associative cache tag info changes at set level so in tag directory of associative cache tag info wil b present only for each set.
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Re: CS 2012: Set A, Question 0

Postby nikhilbhr » Mon Feb 13, 2012 6:14 pm

Priyankadevesh wrote:@t4targate
i agree that tag info is for each line but in set associative cache tag info is same for each line within a set and
question is abt tag directory means how many tag entries wil b in tag directory.at direct mapped cache tag info changes at line level so in tag directory of direct mapped cache tag info is present for each line,but in case of associative cache tag info changes at set level so in tag directory of associative cache tag info wil b present only for each set.

thx u saved me
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Re: CS 2012: Set A, Question 0

Postby nikhilbhr » Mon Feb 13, 2012 6:16 pm

please discuss AIMD problem.my answer was 7MSS
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Re: CS 2012: Set A, Question 0

Postby t4tarGATE » Mon Feb 13, 2012 6:20 pm

nikhilbhr wrote:please discuss AIMD problem.my answer was 7MSS

mine too.. 7mss
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Re: CS 2012: Set A, Question 0

Postby nikhilbhr » Mon Feb 13, 2012 8:01 pm

t4tarGATE wrote:
nikhilbhr wrote:please discuss AIMD problem.my answer was 7MSS

mine too.. 7mss

i tried all combination at home and i got 7MSS ..i dont know how they are getting 14MSS
And answer for cycle of length 4 question is not 90 it cant be greater than 45 ..
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