Performance when use a timer vs a lot of thread to listen event changed? - c++

Question

I need listen a lot of (<10) external event send to app and process them. Event can happen every 50ms or can is a hour, can't predetermine time or frequency, depend user. System use pthread on linux 3.6.5, single core cpu, ram 512. Listener must start at begin system and stop at end system, don't delay recive event (in 50ms). Moreover, also have a thread run update UI, 2 thread in threadpool to download.
External event here can is mouse click, keyboard key down/up, on/off LCD, button power, press key ir remote, a file modified, a alarm push by server,..
I consider 2 option, a listener on thread or a timer thread.
can any one please explain efficient of performance with both above away when use on descripted system ? and which one would be a better choise or a new option ?
a listener on a thread
//==================================== option 1: use 1 listener/thread
// i = [0, n]
bool waitForEvent_i(){
// can is poll change on a file description, read on socket
// or pthread_cond_wait a other thread
// ...
}
void thread_i(){
while(waitForEvent_i()){
excute_i();
}
}
void startListener(){
startThread_0();
startThread_1();
....
startThread_n(); // n < 10;
}
a pthread such as timer proactive check all event can
//================================== option2: use timer to interval check
class Task{
public:
void run(){
// check if have change, call excute_i()
}
};
void timer_thread(timeout){
while(1){
while(!queue.empty()}
{
task = queue->getTask();
task->run();
usleep(timeout - task->timeExcuted()); // suppose, timeExcuted < timeout
}
usleep(timeout);
}
}
void startTimer(){
start_Timer_thread();
}