getConns() is now responsible for returning both stable and unstable
conns. conn and measureFn are now passed together via connAndMeasureFn.
newConnAndMeasureFn() is responsible for constructing them.
TCP measurement timeouts are adjusted to more closely match netcheck.
Updates tailscale/corp#22114
Signed-off-by: Jordan Whited <jordan@tailscale.com>
'stun' has been removed from metric names and replaced with a protocol
label. This refactor is preparation work for HTTPS & ICMP support.
Updates tailscale/corp#22114
Signed-off-by: Jordan Whited <jordan@tailscale.com>
stunstamp timestamping includes userspace and SO_TIMESTAMPING kernel
timestamping where available. Measurements are written locally to a
sqlite DB, exposed over an HTTP API, and written to prometheus
via remote-write protocol.
Updates tailscale/corp#20344
Signed-off-by: Jordan Whited <jordan@tailscale.com>