On Sat, May 28, 2011 at 22:06, Marcus D. Leech <[email protected]> wrote: > I evaluated latency of a FIFO (actually an ordinary pipe, but the kernel > mechanisms are identical), and measured 30usecs average on my > 1.2GHz AMD Phenom system with plenty 'o memory. > > I sent timestamps across the FIFO (struct timeval), and the reader grabbed > the local time of day, and computed the difference. There's > a fair amount of uncertainty on the reader due to gettimeofday() call > overhead. But 30usec on a wimpy CPU is certainly comfortably > below 1msec.
gettimeofday() is a fast function. But if you want real high-fidelity - read CPU clock counter. Just make sure your app runs on a one selected core. Could you post your app and raw results? I'm interested in min/mean/max values and distribution graphs. Because max values do play role when playing with real-time. -- Regards, Alexander Chemeris. _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
