Really simple question…
See the image above for clear understanding of the organisation.
First we need to calculate number of block address a single block can hold
= Block Size/ Block address size
Now just calculate the total number if blocks in the system
= 8 direct pointers + 2 single indirect pointer + 4 double indirect pointer + 1 triple indirect pointer
= 8 + 2 * 1024 + 4 * 1024 * 1024 + 1 * 1024 * 1024 * 1024
Now we have total number of blocks. Just calculate total size by multiplying it with block size
= (8 + 2 * 1024 + 4 * 1024 * 1024 + 1 * 1024 * 1024 * 1024) * 4KB
Yes 4TB to be approx. Rest factors wont be that significant. But if exact is asked then you have to evaluate it.
i am confused when to use direct pointer or indirect pointer
It will be mentioned in the question i guess.