From: "Scott J. Villers" <villers@cae.wisc.edu>
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To: wkalfayy@students.wisc.edu
cc: cs537-2list@cs.wisc.edu
Subject: Re: [cs537-2] Midterm exam
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On Wed, 18 Mar 1998 wkalfayy@students.wisc.edu wrote:
>
> Can someone be gracious to send an email to the class list about what Prof.
> Cao said about the midterm exam in the last review session?  I'm sure it
> would be appreciated by a lot of people.
> 

/*  DISCLAIMER
These are from notes I took on Thursday and are for reference only.
Please do not complain to me later if I missed something.  
*/

//
//Introduction to Operating Systems
//

-manage resources, tasks
-protect data
-4 things operating system does
-kernel/user mode differences
	ex.=>  shell-user mode, compiler-user mode, kernel-kernel mode
-batch systems, time sharing
-machine organization
-handling i/o

//
//Processes
//

-how are they different from a program?
-pc, address space, registers
-accounting information
-process control block (PCB)
-states
	--running
	--ready
	--blocked
	--finished
-operations
-what makes state change
-how created with fork() hierarchy

//
//Synchronization
//

-scheduling of processes
-motivation
-solutions: need hardware help
	--test_and_set instruction
-how to implement critical sections
-what are critical sections?
-semaphores:
	--p() and v() operations
	--bounded buffer problem, reader/writer problem
	--initializing to 0, 1, 2, etc.
***THERE WILL BE NO FIFO READERS/WRITERS PROBLEMS ON THE EXAM***
-monitors:
	--conditional variables
		-process waken up gets CPU
	--how to implement monitors with semaphores
	--how to implement semaphores with monitors

//
//Deadlocks
//

-what are deadlocks?
-4 conditions where deadlock occurs
-how to solve:
	--prevention, avoidance
		-what are mechanisms?
	--recovery methods
-how to prevent:
	--order of operations
	***BANKER'S ALGORITHM NOT ON EXAM***

//
//CPU Scheduling
//

kernel does this
-relinquishing CPU
	--timer interrupt
	--process finishes i/o
-preemptive scheduling
	--round robin
	--priority queue
	--priority scheme
-nonpreemptive scheduling
	--FCFS
	--shortest job first
/*  WILL BE ON THE EXAM FOR SURE!!
	
  -priority inversion
	--how it occurs
	--how to solve
  -priority inheritance

*/

//
//Memory Management
//

-virtual addresses
-virtual/physical page
-draw diagram of page translation including TLB
-page table entry:
	--pid, vpn, ppn
		-before pid, had to clear or 'flush' TLB
		 upon process switching
-demand paging
	--steps involved
	--valid bit
-handling page faults
	--malloc/brk: allocate memory
	--page replacement
-initializing pages
	--from disk
	--'first touch': assign to all zeros
-copy of page on disk
-swap space
	--holds copies of virtual pages
-swap allocation
	--specify where swap space should be in memory
-page replacement algorithms
	--LRU
	--LFU
	--random
	--FIFO
	--MIN/optimal/Belady's algorithm: farthest in the future