Iago uses Common Metrics to record its metrics. If you are using env.local, then the default place for this is
http://localhost:9992/admin/metrics.json?pretty=true
Request latency is the time it takes to queue the request for sending until the response is received. See the Finagle User Guide for more about the individual metrics.
Other metrics of interest:
| Statistic | Description |
|---|---|
connection_duration |
duration of a connection from established to closed? |
connection_received_bytes |
bytes received per connection |
connection_requests |
Number of connection requests that your client did, ie. you can have a pool of 1 connection and the connection can be closed 3 times, so the "connection_requests" would be 4 (even if connections = 1) |
connection_sent_bytes |
bytes send per connection |
connections |
is the current number of connections between client and server |
handletime_us |
time to process the response from the server (ie. execute all the chained map/flatMap) |
pending |
Number of pending requests (ie. requests without responses) |
request_concurrency |
is the current number of connections being processed by finagle |
request_latency_ms |
the time of everything between request/response. |
request_queue_size |
Number of requests waiting to be handled by the server |