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I have attached the problem below

Consider a 512-KByte cache with 64-word cachelines (a cacheline is also known as a cache block, each word is 4-Bytes). This cache uses write-back scheme, and the address is 32 bits wide.

enter image description here

Let's try to start doing the first row. To find the Cachline index, I would have to know the number of cachelines in the cache. I don't know that. The problem doesn't provide any information about the cache that is being used. It's going to be a Miss since at the beginning the cache is empty. It wasn't modified because the request is to read. For the tag, I would have to know what's the bit size of the address , but in this case it's in hex. What's data?. what is caused replace? what is write-back to Memory?. It would be nice if someone can do the first two rows for me and go through every step in this process. I would do the other ones. I would like the first two rows to be done because there are two different types of request, read and write. I need orientation. It would be good as well if someone can point out the resources to understand this question.

Thanks!!!

I have updated the thread

In previous computations, I got that cache offset is 8 bits, cache index is 11 bits and the tag is 13 bits. I converted 0x128 to binary and got 0b100101000. This implies that the cacheline index is 1. The requested address is 0x28 and the tag is 0x0, however; I still can't understand what data, caused replace and write-back to memoery means.

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  • $\begingroup$ what is the data column? and is it a replace in the cache or in memory? $\endgroup$ – TheMathNoob Nov 12 '16 at 6:27
  • $\begingroup$ I did what you said and got all tags and indexes different. There is clearly something wrong. I think that there is a replace if the indexes and tags are the same. $\endgroup$ – TheMathNoob Nov 12 '16 at 6:38
  • $\begingroup$ Don't use images as main content of your post. This makes your question impossible to search and inaccessible to the visually impaired; we don't like that. Please transcribe text and mathematics (note that you can use LaTeX) and don't forget to give proper attribution to your sources! $\endgroup$ – Raphael Nov 12 '16 at 7:21
  • $\begingroup$ The title you have chosen is not well suited to representing your question. Please take some time to improve it; we have collected some advice here. Thank you! $\endgroup$ – Raphael Nov 12 '16 at 7:21
  • $\begingroup$ @tHEMathNoob yes indeed you are correct the conflict arises when the index bits are same. The index bits determine where in the cache the block goes. $\endgroup$ – Shubham Singh rawat Nov 12 '16 at 7:21

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