BackOff Alg functionality

Question 1

What does a higher number of unsuccessful tries mean in a lock? what should it do incase of a backoff?

Answer 1

There is high contention
backoff longer

Question 2

Lock-step

Answer 2

When all threads backs off the same amount of time

Question 3

How should lock-step be avoided

Answer 3

threads should back off for a random amount of time

Question 4

What should a thread do if i tries and fails to get a lock?

Answer 4

double back-off time, up to a fixed max

Question 5

how does the lock look of the Backoff lock?

Answer 5

public void lock() {
int delay = MIN_DELAY;
while (true) {
while (state.get()) {}
if (!lock.getAndSet(true))
return;
sleep(random() % delay);
if (delay < MAX_DELAY)
delay = 2 * delay;
}}