lightswitch05

Using the same receiver, but with a PPS wire to a GPIO pin on a raspberry pi, I get +/- 5µs jitter.

> While this driver can discipline the time and frequency relative to the PPS source, it cannot number the seconds. For this purpose an auxiliary source is required;

And so (with NTPsec), you need to define two sources even though it’s coming from the same device. One for the PPS signal for clock discipline, the other for the clock value.

> refclock pps ppspath /dev/gpspps0 prefer

> refclock nmea baud 57600 prefer

I’ve messed around with this on a couple different GPS chips. I’ve found improvements can be made by increasing the baud rate to the maximum supported. 9600 tends to be the default, but 57600 works a lot better. Also, disable all NMEA sentences except the one you are using. Finally ramp up the update interval to be much more often. The default tends to be every 1000 milliseconds, but 100 milliseconds works better for less jitter. I’ve been using NTPsec, not Chrony, so maybe there are more nuances.

Shameless promotion time, I have a little utility that can check a node version for CVEs or EOL:

    npx node-version-audit@latest --fail-security

    docker run --rm -t lightswitch05/node-version-audit:latest --version=$(node -e "console.log(process.versions.node)")

Anyways, after running for three years, I thought it would be fun to put together some data. The most interesting one is that PHP Version Audit has a median CVE discovery of 5 hours after the PHP announcement. In contrast, the NVE CVE Database has a median of 260 hours - or almost 11 days. Of course the NVE CVE Database has all sorts of information like a vulnerability score, so maybe it’s an apples vs. oranges comparison. Anyways, I hope someone else finds this interesting :)

If you think PHP Version Audit is interesting, there is also Node Version Audit[0] that I released earlier this year.