Re: [Linuxptp-users] Fw: “Resource temporarily unavailable” errors during flood ping test

[Richard C. <ric...@gm...>]

On Tue, Oct 30, 2012 at 05:28:46PM +0000, Keller, Jacob E wrote:

> I think we can get PTP4l to work right even under those scenarios,
> but right now it is horribly annoying that practically everyone has
> to change the value if they ever have stress when ptp is running.

[ I don't have this problem on the hardware that I use most often.
  We can increase the default if you want. ]

We can get ptp4l to transmit asynchronously, but we can't fix the
hardware.  For this reason I remain convinced that we must block and
wait for the time stamp.  If you accept this premise, then you also
must accept the idea of a timeout or retry count, since time stamps
can get lost. There is a trade off between wanting to wait long enough
(hardware specific) and wanting to give up ASAP when a time stamp goes
missing.

We could change the counter to a time value to be compared against
CLOCK_MONOTONIC, but that is only a cosmetic change.

> I like the idea of architecting it to use select and a delay value,
> so I'll try to see how difficult that would be.

Be my guest ;)

I tried once to fixup ptpd like this, and I didn't get very far.

Thanks,
Richard