// checkFailedUnlocks determines whether we have sufficiently unlocked all
// resources to ensure no deadlocks for future callers
func checkFailedUnlocks(locks []string, tolerance int) bool {
	unlocksFailed := 0
	for lockID := range locks {
		if isLocked(locks[lockID]) {
			unlocksFailed++
		}
	}

	// Unlock failures are higher than tolerance limit
	// for this instance of unlocker, we should let the

     *
     * @param username the username to unlock
     * @return true if account was unlocked, false if not found
     */
    public boolean unlockAccount(String username) {
        AccountAttempts account = accountAttempts.get(username);
        if (account != null) {
            account.reset();
            log.info("Manually unlocked account: {}", username);
            return true;
        }
        return false;
    }

An unsuccessful call has no synchronizing effect at all.
As far as the memory model is concerned,
<code>l.TryLock</code> (or <code>l.TryRLock</code>)
may be considered to be able to return false
even when the mutex <i>l</i> is unlocked.
</p>

<h3 id="once">Once</h3>

<p>
The <code>sync</code> package provides a safe mechanism for
initialization in the presence of multiple goroutines
through the use of the <code>Once</code> type.

      List<LockGraphNode> acquiredLockList = requireNonNull(acquiredLocks.get());
      LockGraphNode node = lock.getLockGraphNode();
      // Iterate in reverse because locks are usually locked/unlocked in a
      // LIFO order.
      for (int i = acquiredLockList.size() - 1; i >= 0; i--) {
        if (acquiredLockList.get(i) == node) {
          acquiredLockList.remove(i);
          break;
        }
      }

limitation.

==== Keystore Password

In FIPS 140-2 mode, the elasticsearch keystore needs to be password protected with a password
of appropriate length. This is handled automatically in `fips.gradle` and the keystore is unlocked
on startup by the test clusters tooling in order to have secure settings available. However, you
might need to take into consideration that the keystore is password-protected with `keystore-password`