1. A 32-bit computer has two selector channels and one multiplexor channel. Each
selector channel supports two hard disks and two DVDs units. The multiplexor channel
has two printers, three VDT terminals connected to it. Assume the following transfer
Disk drive 800 Kbytes/s
DVD drive 700 Kbytes
Printer 20 Kbytes/s
VDT 30 Kbytes/s
Estimate the maximum aggregate I/O transfer rate in this system. Show how you
2. Given the following set of events, show which routines the CPU is executing for times 0
to 150 ms. Each handler routine (with its interrupt request) takes 25 ms to complete. The
priority of the interrupts ranges from IRQ6 as the highest priority interrupt to IRQ0 as
the lowest priority interrupt.
0 ms Start of main program
10 ms IRQ1
25 ms IRQ3
35 ms IRQ4
45 ms IRQ6
55 ms IRQ2
0 ms: Start of Main Program
10 ms: IRQ1
3. Why do you think the term random access device is something of a misnomer for disk
4. What are the advantages and disadvantages of having a small number of sectors per disk
This material may consist of step-by-step explanations on how to solve a problem or examples of proper writing, including the use of citations, references, bibliographies, and formatting. This material is made available for the sole purpose of studying and learning - misuse is strictly forbidden.
1) Answer: First, we recall that one selector channel can only serve one device/component at a time. Because we are asked to estimate the maximum aggregate I/O transfer rate in this system and the disk drive has higher transfer rate than the DVD unit, it means that we compute the required transfer rate using the disk drive for each selector channel. The remaining devices (printers and VDT terminals) can be served by...