On 05/29/2011 10:22 AM, Alexander Chemeris wrote: > On Sun, May 29, 2011 at 03:05, Marcus D. Leech <[email protected]> wrote: >> On 05/28/2011 04:28 PM, Alexander Chemeris wrote: >>>> >>>> So, while this method is simple and good for non-realtime >>>> applications, it doesn't fit our needs. It may be usable for PHY<->MAC >>>> interaction, but even here I'm not sure it would work well. >>>> >>>> PS I test on Core 2 Duo 1.6 GHz with all the GUI stuff running. >>> >>> Ok, setting CPU affinity and cutting off startup artifacts definitely >>> helps. >>> Results are in attachment. >>> Still you can see quite some uncertainty. >>> >> OK, so a roughly 3:1 improvement in peak latency, and somewhat better >> predicability. >> >> But I'd still counter-assert, to your assertion, that latencies in the >> 10s-of-usec are entirely acceptable for >> a wide-range of "real-time" applications, even with occasional latency >> excursions that increase the variability >> by 50:1 or so. >> >> I can well imagine that they aren't acceptable for *your* application. I >> mean, if all applications were the same, it would >> be a very boring world, with most of us working at fast-food restaurants >> :-) >> >> But I'll stand by my original suggestion that use of FIFOs are an acceptable >> technique for a wide variety of applications, including >> "real-time" applications, depending on constraints and requirements. > > Sure, I don't say that no one should use queues :) > I just want to say that it may not be suitable for applications with > more tight requirements - i.e. some alternative may be needed. > > But to say truth - I'm surprised by their performance, I thought it > would be much worse. So it may be a good starting point from which we > could refine later. >
Linux' pipe implementation is known to be quite slow. I would suggest to use UNIX sockets instead. They should perform much better in terms of latency and performance. Cheers, Andre _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
