GDI3 Kram

leistungsberechnung.txt

T - CPU-Zeit in Sekunden
f - Taktfrequenz in Zyklen pro Sekunde
t - Taktzykluszeit in Sekunden pro Zyklus
MIPS - Millionen von Instruktionen pro Sekunde
CPI - mittlere Anzahl Zyklen pro Instruktion
B - Anzahl Instruktionen
Z - CPU-Zeit in Zyklen

T = Z * t
CPI = Z / (T * MIPS * 10^6)
T = B * CPI / f
B = T * MIPS * 10^6
Z = T * CPI * MIPS * 10^6

osi.txt

Alle Priester saufen Tequila nach der Prädigt

7. Application
6. Presentation
5. Session
4. Transport
3. Network
2. Data
1. Physical

philosopher.c

// Andrew S. Tanenbaum: Modern Operating Systems 3e p. 164

#define N		5
#define LEFT		(i+N-1)%N
#define RIGHT		(i+1)%N
#define THINKING	0
#define HUNGRY		1
#define EATING		2
typedf int semaphore;
int state[N];
semaphore mutex = 1;
semaphore s[N];

void philosopher(int i)
{
	while (TRUE) {
		think();
		take_forks(i);
		eat();
		put_forks(i);
	}
}

void take_forks(int i)
{
	down(&mutex);
	state[i] = HUNGRY;
	test(i);
	up(&mutex);
	down(&s[i]);
}

void put_forks(i)
{
	down(&mutes);
	state[i] = THINKING;
	test(LEFT);
	test(RIGHT);
	up(&mutex);
}

void test(i)
{
	if (state[i] == HUNGRY && state[LEFT] != EATING && state[RIGHT] != EATING) {
		state[i] = EATING;
		up(&s[i]);
	}
}

rekursion.asm

josephus:	
		sub	$sp, $sp, 12
		sw	$ra, 8($sp)		#sichere ruecksprungadresse
		sw	$a1, 4($sp)		#sichere K
		sw	$a0, 0($sp)		#sichere N

		seq	$t0, $a0, 1
		beqz	$t0, rekursion		#N ist != 1, also rekursion
		li	$v0, 0
		jr	$ra

rekursion:
		sub	$a0, $a0, 1		#dekrementiere N um 1
		jal	josephus

		lw	$a0, 0($sp)		#hole N
		lw	$a1, 4($sp)		#hole K
		lw	$ra, 8($sp)		#hole ruecksprungadresse
		add	$sp, $sp, 12

zweierpotenzen.txt

2^3 - 8
2^4 - 16
2^5 - 32
2^6 - 64
2^7 - 128
2^8 - 256
2^9 - 512
2^10 - 1024