Hi Miroslav & Richard,
Not sure whether I have understood your concern here. High quality PLLs offer stepping in pico seconds. 512 sync packets are a reasonable rate for frequency corrections. In case of ToD, the fractional HW arithmetic (2^-16) can give you capability to achieve the highest accuracy possible, if the stack can supply such fine-grained values. As for 'what is that supposed to achieve?', in ideal scenario, targeting 50pbb for CDMA is what I look at. I am further trying to analyze SyncE requirements from 1588 perspective, which seems too tough at this moment due to OS scheduling jitter itself. Please correct me as appropriate and pour in your thoughts. Thanking you in anticipation, Regards, Chandra (c) : 0175508142 (O): 701.6412 "Knowledge speaks, Wisdom listens" -----Original Message----- From: Miroslav Lichvar [mailto:[email protected]] Sent: Wednesday, March 18, 2015 12:44 AM To: Richard Cochran Cc: Chandra Mallela; [email protected] Subject: Re: [Linuxptp-users] Expected throughput of the ptp4l On Tue, Mar 17, 2015 at 05:32:38PM +0100, Richard Cochran wrote: > On Tue, Mar 17, 2015 at 04:15:46PM +0000, Chandra Mallela wrote: > > Could you elaborate your experience with the ptp4l performance? > > I never tried 512 Syncs per second, nor do I see any reason to run > such a high rate. What is that supposed to achieve? I'm wondering that too. Even if we assume a very unstable clock, the clock resolution and jitter would have to be somewhere in low picoseconds to -9 provide any theoretical improvement over -8. -- Miroslav Lichvar ________________________________ Confidentiality Notice. This message may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any use, disclosure, dissemination, distribution, or copying of this message, or any attachments, is strictly prohibited. If you have received this message in error, please advise the sender by reply e-mail, and delete the message and any attachments. Thank you. ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Linuxptp-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linuxptp-users
