CS501 Advance Computer Architecture GDB Solution Spring 2014

All students of CS501 are directed to participate in the GDB that will be opened from 7th August 2014 to 8thAugust 2014.
GDB answer via email or through MDB will not be accepted.

Note: Your answer should not be more than 300 words.
In computer architecture why does a “system interface unit” provide separate queues for “read” and “write” transactions? Is it possible for a “write queue” to directly execute without interference of “read queue”?

Solution: Read requests are generally stalling the processor (however see pre-fetching) and thus need to be given priority. The SIU will manage separate queues for read and write transactions – taking requests from the read queue in preference to those in the write queue.  Transactions in the write queue are only selected for execution if the read queue is empty. This is a key function of the SIU – giving priority to read transactions that could block the CPU.