Cheat Sheet
Process comprises of 3 main parts:
Processor State - registers, program counter
OS Resources - open files, network sockets, etc
Address Space - main memory a process accesses; code, variables, stack
Scheduling
SJF optimizes the average waiting time.
EDF minimizes lateness and is guaranteed to meet deadlines if deadlines can
be met.
RMS: highest static priority = smallest period for preemptive periodic processes;
RMS guarantees C_i / T_i Counting Semaphore
binary_semaphore s1 = 1, s2 = 0;
int c; // set to initial value for S.
wait(S): signal(S):
wait(s1);
c--; wait(s1);
if (c frames
Logical Memory -> pages
PTBR: Page Table Base Register - points to page table
PTLR: Page Table Length Register - holds the size of page table
Associative Memory / Translation Look Aside Buffers (TLBs)
Effective Access Time (EAT)
Hit Ratio = a
Memory Access Time = t
TLB search time = d
EAT = a(m+d) + (1-a)(2m+d)