COP 4600 /EEL 4882Project 4

Task

I/O Request processing– SIO– WIO

Process state– Active (only one)– Ready (multiple)– Block– Done

University of Central Florida

University of Central Florida

Input

Input files are the same

This time we need actually run instructions inside program script

Simulation of SIO, WIO instruction

Instruction “SIO” and “WIO”

ReviewSIO 40DSK2 10 -- Start Dsk2, requesting 10 bytes……WIO 0REQ [1,1] -- See if I/O request at [1,1] has finished, if not, block

How do we handle that?– Whenever we execute SIO, generate EIO event in a future time– When WIO occur first:

– Check if I/O request still there, if so, block– When EIO occur first:

– Remove I/O request

University of Central Florida

Interrupt

University of Central Florida

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Obj1.c: Get EVENT from event queue:

LOGONSTARTIOWAITIOENDIO

PGMEND

Simulator.c: Call event handler:

Logon_ServiceSio_ServiceWio_ServiceEio_ServiceEnd_Service

Events

Logon– Generated by Obj1.c: Load_events()

– When read logon.dat

SIO/WIO/PGMEND– Generated by Obj2.c:Cpu()– When execute SIO/WIO/END instruction

EIO– Generated by Obj4.c:Sio_Service()

University of Central Florida

Scheduler

University of Central Florida

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Select process to run

P2 ‘B’ P5 ‘B’

P4 ‘R’ P1 ‘R’ P3 ‘R’Ready Queue

Which Process to run: FCFS

Dispatcher

University of Central Florida

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Obj2.c: XPGM()

Obj2.c: Cpu()

Run one or several instructions (one cpu burst)

Event Flow

University of Central Florida

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Event Queue:

Logon Logon Logon Logon

Editor Editor LogoffScript:

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

Obj3:Logon_Service

Obj3: Next_pgm

SIO

Event Flow

University of Central Florida

Event Queue:

Logon SIO Logon

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Printer LogoffScript:

P2:SIO 27DISK 3000SIO 15PRNT 100END 30

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

SIO

Event Flow

University of Central Florida

Event Queue:

SIO Logon SIO

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Obj4:SIO_Service

EIO

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

WIO

Event Flow

University of Central Florida

Event Queue:

Logon SIOWIO

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

I/O have not finished

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

Block

P2:SIO 27DISK 3000SIO 15PRNT 100END 30

Obj4:WIO_Service

EIO

PRNT P1

Event Flow

University of Central Florida

Event Queue:

Logon SIO

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

EIO

Obj4:EIO_Service

PRNT P1

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

Ready

P2:SIO 27DISK 3000SIO 15PRNT 100END 30

Ready

Active

WIO

Event Flow

University of Central Florida

Event Queue:

SIO WIO

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

Logon

Printer LogoffScript: Editor

P3:SIO 10DISK 1000WIO 0REQ [0,1]END 37

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,1]END 17

Ready queue:

P2

P3

PGMEND

Event Flow

University of Central Florida

Event Queue:

SIO WIO

Interrupt() Interrupt_Handler()

Scheduler() Dispatcher()

PGMEND

Obj3: End_Service

P1:SIO 23PRNT 100SIO 32DISK 300WIO 0REQ [0,3]END 17

Editor Editor LogoffScript:

Obj3: Next_pgm P4:SIO 18PRNT 200SIO 5PRNT 200WIO 19REQ [0,1]END 13

Ready Queue P2 P3 P4

Device List

University of Central Florida

DSK2

DSK1

PRNT

R1 R5

R3

R7

R6

SIO(R5) SIO(R7) EIO(R1)

Deadline

Deadline is Arp 4 (Friday) midnight

Late assignments are accepted five days after the due date with a penalty of 20 % off. After five days, assignments will not be accepted. The grade for those assignments will be zero.

University of Central Florida