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[CT420]: Finish merged.c

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Aindréas Ó hAodha
2025-03-19 07:45:33 +00:00
parent 2ca61c07de
commit c8af0f8c2e
1 changed files with 36 additions and 55 deletions
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91
year4/semester2/CT420/assignments/assignment2/code/merged.c
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@ -12,7 +12,7 @@
#include <string.h>
#include <limits.h>
#define ITERATIONS 1000
#define ITERATIONS 10000
#define NS_PER_SEC 1000000000L
timer_t timer_id;
@ -20,6 +20,19 @@ volatile sig_atomic_t timer_expired = 0;
volatile sig_atomic_t signal_received = 0;
struct timespec start, end, sleep_time;
void save_results(const char *filename, long long *data) {
FILE *file = fopen(filename, "w");
if (!file) {
perror("fopen");
exit(EXIT_FAILURE);
}
fprintf(file, "Iteration,Latency/Jitter (ns)\n");
for (int i = 0; i < ITERATIONS; i++) {
fprintf(file, "%d,%lld\n", i, data[i]);
}
fclose(file);
}
void signal_handler(int signum) {
signal_received = 1;
clock_gettime(CLOCK_MONOTONIC, &end);
@ -47,11 +60,7 @@ void lock_memory() {
}
void benchmark_nanosleep() {
// struct timespec start, end, sleep_time;
long long total_jitter = 0;
long long max_jitter = 0;
long long min_jitter = LLONG_MAX;
long long jitter_data[ITERATIONS];
sleep_time.tv_sec = 0;
sleep_time.tv_nsec = 1000000; // 1 ms
@ -60,25 +69,13 @@ void benchmark_nanosleep() {
nanosleep(&sleep_time, NULL);
clock_gettime(CLOCK_MONOTONIC, &end);
long long elapsed = (end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec);
long long jitter = elapsed - sleep_time.tv_nsec;
total_jitter += llabs(jitter);
if (jitter > max_jitter) max_jitter = jitter;
if (jitter < min_jitter) min_jitter = jitter;
jitter_data[i] = ((end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec)) - sleep_time.tv_nsec;
}
printf("Nanosleep Benchmark:\n");
printf("Average jitter: %lld ns\n", total_jitter / ITERATIONS);
printf("Max jitter: %lld ns\n", max_jitter);
printf("Min jitter: %lld ns\n", min_jitter);
save_results("nanosleep.csv", jitter_data);
}
void benchmark_signal_latency() {
long long total_latency = 0;
long long max_latency = 0;
long long min_latency = LLONG_MAX;
long long latency_data[ITERATIONS];
signal(SIGUSR1, signal_handler);
for (int i = 0; i < ITERATIONS; i++) {
@ -86,25 +83,14 @@ void benchmark_signal_latency() {
kill(getpid(), SIGUSR1);
while (!signal_received);
long long latency = (end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec);
total_latency += latency;
if (latency > max_latency) max_latency = latency;
if (latency < min_latency) min_latency = latency;
latency_data[i] = (end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec);
signal_received = 0;
}
printf("\nSignal Latency Benchmark:\n");
printf("Average latency: %lld ns\n", total_latency / ITERATIONS);
printf("Max latency: %lld ns\n", max_latency);
printf("Min latency: %lld ns\n", min_latency);
save_results("signal_latency.csv", latency_data);
}
void benchmark_timer() {
long long total_jitter = 0;
long long max_jitter = 0;
long long min_jitter = LLONG_MAX;
long long jitter_data[ITERATIONS];
struct sigevent sev;
sev.sigev_notify = SIGEV_SIGNAL;
sev.sigev_signo = SIGRTMIN;
@ -119,7 +105,6 @@ void benchmark_timer() {
its.it_value.tv_sec = 0;
its.it_value.tv_nsec = 1000000; // 1 ms
its.it_interval = its.it_value;
signal(SIGRTMIN, timer_handler);
if (timer_settime(timer_id, 0, &its, NULL) == -1) {
@ -128,32 +113,27 @@ void benchmark_timer() {
}
clock_gettime(CLOCK_MONOTONIC, &start);
for (int i = 0; i < ITERATIONS; i++) {
// while (!timer_expired);
while (!timer_expired) {
struct timespec ts = {0, 100};
nanosleep(&ts, NULL);
}
while (!timer_expired);
clock_gettime(CLOCK_MONOTONIC, &end);
long long elapsed = (end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec);
long long jitter = elapsed - its.it_interval.tv_nsec;
total_jitter += llabs(jitter);
if (jitter > max_jitter) max_jitter = jitter;
if (jitter < min_jitter) min_jitter = jitter;
jitter_data[i] = ((end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec)) - its.it_interval.tv_nsec;
timer_expired = 0;
start = end;
}
save_results("timer.csv", jitter_data);
}
printf("\nTimer Benchmark:\n");
printf("Average jitter: %lld ns\n", total_jitter / ITERATIONS);
printf("Max jitter: %lld ns\n", max_jitter);
printf("Min jitter: %lld ns\n", min_jitter);
void benchmark_usleep() {
long long jitter_data[ITERATIONS];
timer_delete(timer_id);
for (int i = 0; i < ITERATIONS; i++) {
clock_gettime(CLOCK_MONOTONIC, &start);
usleep(1000); // 1 ms
clock_gettime(CLOCK_MONOTONIC, &end);
jitter_data[i] = ((end.tv_sec - start.tv_sec) * NS_PER_SEC + (end.tv_nsec - start.tv_nsec)) - 1000000;
}
save_results("usleep.csv", jitter_data);
}
int main() {
@ -163,6 +143,7 @@ int main() {
benchmark_nanosleep();
benchmark_signal_latency();
benchmark_timer();
benchmark_usleep();
return 0;
}