drop addr and port from Endpoint.Latest map

[rade]

The information is constant and already present in the id, so we can extract it from there.

That reduces the report size and improves report encoding/decoding performance. It should reduce memory usage too and improve report merging performance too.

NB: Probes with this change are incompatible with old apps.

[rade]

I grabbed a recent prod report and then did this...

$ jq 'del(.Endpoint.nodes[].latest.addr,.Endpoint.nodes[].latest.port)' prod-on-dev-report.json > prod-on-dev-report-trimmed.json
$ extras/copyreport/copyreport prod-on-dev-report.json prod-on-dev-report.msgpack.gz
$ extras/copyreport/copyreport prod-on-dev-report-trimmed.json prod-on-dev-report-trimmed.msgpack.gz
$ ls -s prod-on-dev-report*.msgpack.gz
2788 prod-on-dev-report.msgpack.gz
2364 prod-on-dev-report-trimmed.msgpack.gz
$ bc <<< "scale=3;2364/2788"
.847
$ time GOMAXPROCS=1 extras/copyreport/copyreport prod-on-dev-report.msgpack.gz /tmp/report.msgpack.gz

real	0m1.637s
user	0m1.584s
sys	0m0.052s
$ time GOMAXPROCS=1 extras/copyreport/copyreport prod-on-dev-report-trimmed.msgpack.gz /tmp/report.msgpack.gz

real	0m1.449s
user	0m1.380s
sys	0m0.052s
$ bc <<< "scale=3;1.449/1.637"
.885

So report size is down 15% and encode/decode performance is up 12%.

[rade]

To check that I didn't break anything, I ran

$ prog/scope --mode=app --weave=false --app.collector=file:/home/matthias/tmp/prod-on-dev-report.json
$ for r in processes containers pods services hosts; do \
    curl -s http://localhost:4040/api/topology/$r | jq -S '.' > $r.json; \
  done
$ prog/scope --mode=app --weave=false --app.collector=file:/home/matthias/tmp/prod-on-dev-report-trimmed.json
$ for r in processes containers pods services hosts; do \
    curl -s http://localhost:4040/api/topology/$r | jq -S '.' > $r-trimmed.json; \
  done
$ for r in processes containers pods services hosts; do \
    diff -q $r.json $r-trimmed.json
  done

[2opremio]

Good one!