time thread priority + nanosleep

Former-commit-id: c84f296edabc001a1836ab8437f746dcff811148

src/server.cpp

@@ -6068,9 +6068,12 @@ void OnTerminate()
 }
 
 void *timeThreadMain(void*) {
+    timespec delay;
+    delay.tv_sec = 0;
+    delay.tv_nsec = 100;
     while (true) {
         updateCachedTime();
-        usleep(1);
+        clock_nanosleep(CLOCK_REALTIME, 0, &delay, NULL);
     }
 } 
 
@@ -6422,6 +6425,9 @@ int main(int argc, char **argv) {
     serverAssert(cserver.cthreads > 0 && cserver.cthreads <= MAX_EVENT_LOOPS);
 
     pthread_create(&cserver.time_thread_id, nullptr, timeThreadMain, nullptr);
+    struct sched_param time_thread_priority;
+    time_thread_priority.sched_priority = sched_get_priority_max(SCHED_FIFO);
+    pthread_setschedparam(cserver.time_thread_id, SCHED_FIFO, &time_thread_priority);
 
     pthread_attr_t tattr;
     pthread_attr_init(&tattr);