What does your testing show when you don't have
the extra check, i.e.,
struct timespec delay;
struct timespec remain;
delay.tv_sec = microsec / 1000000L;
delay.tv_nsec = (microsec % 1000000L) * 1000;
while (nanosleep(&delay, &remain) == -1 && errno == EINTR)
delay = remain;
This is similar to the first attempt [1],
+pg_usleep_handle_interrupt(long microsec, bool force)
{
if (microsec > 0)
{
#ifndef WIN32
struct timespec delay;
+ struct timespec remaining;
delay.tv_sec = microsec / 1000000L;
delay.tv_nsec = (microsec % 1000000L) * 1000;
- (void) nanosleep(&delay, NULL);
+
+ if (force)
+ while (nanosleep(&delay, &remaining) == -1 && errno == EINTR)
+ delay = remaining;
but Bertrand found long drifts [2[ which I could not reproduce.
To safeguard the long drifts, continue to use the &remain time with an
additional safeguard to make sure the actual sleep does not exceed the
requested sleep time.
[1] https://www.postgresql.org/message-id/7D50DC5B-80C6-47B5-8DA8-A6C68A115EE5%40gmail.com
Regards,
Sami
