Hello.
The problem is only when I use Xenomai linking flags and only with
thestart time. Period is OK.
That aprox. 16s time delay can be "compensated" by substracting of any
number of seconds from the start time.
// Create timer
timer_fd = timerfd_create(CLOCK_MONOTONIC, 0);
// Get current time
struct timespec start;
clock_gettime(CLOCK_MONOTONIC, &start);
// Set periodic
struct itimerspec timer_conf;
memset(&timer_conf, 0, sizeof (timer_conf));
timer_conf.it_value = timespec_add(start, -15 * NANOSEC_PER_SEC);
// compensation of the delay
...
timerfd_settime(timer_fd, TFD_TIMER_ABSTIME, &timer_conf, NULL);
There is strange unexpected difference/time shift between product of
clock_gettime and timerfd_settime. Only with Xenomai posix wrappers.
Best regards
Petr Cervenka
Dne 10.08.2020 v 8:45 Per Oberg napsal(a):
----- Den 7 aug 2020, på kl 17:12, xenomai [email protected] skrev:
Hello.
I have created small example of periodic task in posix.
If I compile it without xenomai it works fine.
When I add Xenomai linking flags, the first tick of periodic task take around
16s. After that it continues as it should.
Used clock type for timer_fd is CLOCK_MONOTONIC. The example should in
attachment.
Do you have any suggestions?
Just had a extremely quick look at it. Are you sure you don't get any rounding
errors when doing your period arithmetics ?
Best regards
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Per Öberg
