Do you have experience with this? Playing around with PTP has been on my TODO list for quite a while, but it seems to be quite a hassle.
At home, I already have a GPS module with its PPS pin connected to an Pi running an NTP server. In my data center, I use clock.sjc.he.net and that's about as good as NTP gets. Certainly good enough for one-way latency measurements.
Are there any SBCs with hardware timestamping and a PPS input? I've heard mixed reviews of the BeagleBone Black as a PTP server. Then again, even if I get that working I have no way to run PTP in the data center since there's no GPS reception in the cabinets.
It _is_ a hassle, and you should have a need for that level of synchronicity. We did it in our team for an in-vehicle network, with the vehicle GPS reciever as the network PTP time master and we figured how to access the ethernet PTP register both from userspace and from the kernel. Kernel for the system clock, user space to avoid latencies from kernel Userland interaction in some high precision real time task. It was a major effort and it required low level hackery way above my personal head.
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Do you have experience with this? Playing around with PTP has been on my TODO list for quite a while, but it seems to be quite a hassle.
At home, I already have a GPS module with its PPS pin connected to an Pi running an NTP server. In my data center, I use clock.sjc.he.net and that's about as good as NTP gets. Certainly good enough for one-way latency measurements.
Are there any SBCs with hardware timestamping and a PPS input? I've heard mixed reviews of the BeagleBone Black as a PTP server. Then again, even if I get that working I have no way to run PTP in the data center since there's no GPS reception in the cabinets.
It _is_ a hassle, and you should have a need for that level of synchronicity. We did it in our team for an in-vehicle network, with the vehicle GPS reciever as the network PTP time master and we figured how to access the ethernet PTP register both from userspace and from the kernel. Kernel for the system clock, user space to avoid latencies from kernel Userland interaction in some high precision real time task. It was a major effort and it required low level hackery way above my personal head.