split-ping is a tool that can tell you what direction packet latency or loss is on. This is handy for network debugging and locating congestion.
It was built as part of a personal blog post: https://blog.benjojo.co.uk/post/ping-with-loss-latency-split
split-ping's binary name is shorted to sping for ease, it's help page is as follows:
$ ./sping -h Usage of ./sping: -clock-is-perfect Enable userspace calibration against Apple's GPS NTP servers (default true) -debug.showslots Show incoming packet latency slots -debug.showstats Show per ping info, and timestamps -listenAddr string Listening address (default "[::]:6924") -peers string List of IPs that are peers -pps.debug Enable debug output for PPS inputs -pps.path string what PPS device to use (default "/dev/pps0") -udp.pps int max inbound PPS that can be processed at once (default 100) -use.pps If to use a PPS device instead of system clock -web.listen-address string Address on which to expose metrics and web interface (default "[::]:9523") -web.telemetry-path string Path under which to expose metrics. (default "/metrics") When viewing the stats via the CLI:
# run this on each host, pointed at the other host as a peer $ ./sping -peers 198.16.109.36 -debug.showstats 2021/03/03 19:04:10 Listening on[::]:9523 it is now: 2021-03-03 19:04:11.000241999 +0000 GMT m=+0.500559754 it is now: 2021-03-03 19:04:12.000174134 +0000 GMT m=+1.500491809 2021/03/03 19:04:12 [198.16.109.36] RX: 8.131386ms TX: 0s [Loss RX: 0/0 | Loss TX 0/0] ...When viewing the stats via the web interface:
$ ./sping -peers 198.16.109.36 $ open http://127.0.0.1:9523/metrics# HELP splitping_latency The latency (in seconds) in each direction # TYPE splitping_latency gauge splitping_latency{direction="rx",host="23.132.96.179"} 0.068701256 splitping_latency{direction="tx",host="23.132.96.179"} 0.066165156 # HELP splitping_loss The loss in each direction # TYPE splitping_loss gauge splitping_loss{direction="rx",host="23.132.96.179"} 0 splitping_loss{direction="tx",host="23.132.96.179"} 0 ... A simple go build in this directory should build sping (after auto-fetching the go modules)