You are designing a write buffer between a write-through L1 cache and a write-back L2 cache. The L2 cache write data bus is 16 B wide and can perform a write to an independent cache address every four processor cycles.

a. How many bytes wide should each write buffer entry be?
b. What speedup could be expected in the steady state by using a merging write buffer instead of a non-merging buffer when zeroing memory by the execution of 64-bit stores if all other instructions could be issued in parallel with the stores and the blocks are present in the L2 cache?
c. What would be the effect of possible L1 misses on the number of required write buffer entries for systems with blocking and non-blocking caches?

7.23 main lab 7 - online shopping cart background this main lab extends the earlier prep lab "online shopping cart part 1". (you should save this as a separate project from the earlier prep lab). you will create an on-line shopping cart like you might use for your on-line purchases. the goal is to become comfortable with setting up classes and using objects. requirements this lab can be done individually or as pair programming. expanded itemtopurchase class (15 points) extend the itemtopurchase class as follows. we will not do unit testing in this lab so we will not be giving you the names of the member functions. create good ones on your own. create a parameterized constructor to assign item name, item description, item price, and item quantity (default values of "none" for name and description, and 0 for price and quantity). additional public member functions set an item description get an item description print the cost of an item - outputs the item name followed by the quantity, price, and subtotal (see example) print the description of an item - outputs the item name and description (see example) additional private data members a string for the description of the item. example output of the function which prints the cost of an item: bottled water 10 @ $1.50 = $15.00 example output of the function which prints the item description: