CPS110:
Address translation
Landon Cox
February 18, 2009
Course administration
 Project 1 drawing to a close
 Two groups with 100% (another is close)
 Four groups > 60 on 1t
 Many others close (40-50 range)
 Some final tips …
Course administration
 What to carefully reread
 Section 4.4 of the spec (ordering stuff)
 Thread implementation slides
 Lock implementation slides
 I see a lot of code that ignore these sources
 Other hints …
Course administration
/*
* Allocate space for thread control block and
* new stack.
*/
try {
thread_ptr = new thread_t;
thread_ptr->stack = NULL;
thread_ptr->stack = new char [stack_size];
} catch(bad_alloc) {
if (thread_ptr != NULL) {
if (thread_ptr->stack != NULL) {
delete [] thread_ptr->stack;
}
delete thread_ptr;
}
return(-1);
}
Course administration
 Project 2 (virtual memory) out next Wednesday
 In some ways easier than P1
 In some ways harder than P1 (not given a solution)
 Next deadline: midterm exam (February 23rd)
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In-class
One sheet (two sides) of notes
No laptops or other electronic resources
Practice exam in discussion section this week
Midterm exam
 What will be covered?
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All threads/concurrency material
Project 1
Lectures
Homework problems
Analysis vs synthesis
 No regurgitation questions
 Analysis questions
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Analyze system/program/design
Trace through program
Compute performance
Determine properties (deadlock, starvation, races)
 Synthesis
 Design/construct a new system/program/design
 I like these more (e.g. learn the most doing projects)
How to study
 Do homework problems
 Understand Project 1
 In groups
 Create and answer questions I might ask
 (you might get lucky; happened in past)
Syntax for programs
 Real or pseudo is fine (just be clear)
 STL is fine
 queue.{push, pop, front, empty}
 Monitors
 Project 1 syntax or OO syntax
 thread_lock (lock_num) or mutex.lock ()
 Semaphores
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OO syntax
sem1.up (), sem1.down (), sem2.up (), …
There is no “getVal” call!
Remember to specify initial value!!
Syntax for traces
 Thread: line number (or range of lines)
1: checkMilk () {
2:
if (noNote) {
3:
leave note
4:
if (noMilk){
5:
buy milk;
6:
}
7:
remove note;
8:
}
9: }
Landon:
Melissa:
Landon:
Melissa:
1-2
1-2
3-6
3-6
On-board review