void* power_measurement(void* arg) {
struct mstimer timer;
// according to the Intel docs, the counter wraps a most once per second
// 100 ms should be short enough to always get good information
init_msTimer(&timer, 100);
init_data();
read_rapl_init();
start = now_ms();
timer_sleep(&timer);
while(running) {
take_measurement();
timer_sleep(&timer);
}
}
int main(int argc, char**argv)
{
printf("starting wrapper\n");
if (argc < 3)
{
printf("Usage: %s <watt_cap> <executable> <args>...\n", argv[0]);
return 1;
}
if (highlander())
{
/* Start the log file. */
int logfd;
char hostname[64];
gethostname(hostname, 64);
char *fname;
int ret = asprintf(&fname, "%s.power.dat", hostname);
if (ret < 0)
{
printf("Fatal Error: Cannot allocate memory for fname.\n");
return 1;
}
logfd = open(fname, O_WRONLY|O_CREAT|O_EXCL|O_NOATIME|O_NDELAY, S_IRUSR|S_IWUSR);
if (logfd < 0)
{
printf("Fatal Error: %s on %s cannot open the appropriate fd.\n", argv[0], hostname);
return 1;
}
logfile = fdopen(logfd, "w");
read_rapl_init();
/* Set the cap. */
watt_cap = strtod(argv[1], NULL);
set_rapl_power(watt_cap, watt_cap);
/* Start power measurement thread. */
pthread_t mthread;
pthread_create(&mthread, NULL, power_set_measurement, NULL);
/* Fork. */
pid_t app_pid = fork();
if (app_pid == 0)
{
/* I'm the child. */
execvp(argv[2], &argv[2]);
return 1;
}
/* Wait. */
waitpid(app_pid, NULL, 0);
sleep(1);
highlander_wait();
/* Stop power measurement thread. */
running = 0;
take_measurement();
end = now_ms();
/* Output summary data. */
char *msg;
ret = asprintf(&msg, "host: %s\npid: %d\ntotal: %lf\nallocated: %lf\nmax_watts: %lf\nmin_watts: %lf\nruntime ms: %lu\n,start: %lu\nend: %lu\n", hostname, app_pid, total_joules, limit_joules, max_watts, min_watts, end-start, start, end);
if (ret < 0)
{
printf("Fatal Error: Cannot allocate memory for msg.\n");
return 1;
}
fprintf(logfile, "%s", msg);
fclose(logfile);
close(logfd);
shmctl(shmid, IPC_RMID, NULL);
shmdt(shmseg);
}
else
{
/* Fork. */
pid_t app_pid = fork();
if (app_pid == 0)
{
/* I'm the child. */
execvp(argv[2], &argv[2]);
return 1;
}
/* Wait. */
waitpid(app_pid, NULL, 0);
highlander_wait();
}
return 0;
}
