Apply metrics in p2p package

[trinhdn2]

Prerequisite

• Refactor metrics package with Prometheus and InfluxDB support #428

Checklist

• Measures the Snappy compressed wire traffic belonging to individual subprotocols, down to the message type level.
• Adds metrics for the p2p dialer, which gives us visibility into the quality of the dial candidates given to us by our discovery methods.
• Adds similar to p2p/metrics metered connection for discover module. The aim is to have more detailed information about network usage which currently isn't tracked for discV4.

Added metrics:

• discover/bucket/{index}/count - the number of nodes in bucket index
• p2p/{ingress|egress}/eth/{version}/{msgCode} - message type level metrics from eth62, eth63
• p2p/peers - active peer gauge
• p2p/serves - serve meter
• p2p/serves/success - serve success meter
• p2p/dials/success - the total number of dials that result in a peer being added to the peerset
• p2p/dials/error/connection - unable to initiate TCP connection to target
• p2p/dials/error/saturated - local client is already connected to its maximum number of peers
• p2p/dials/error/known - dialing an already connected peer
• p2p/dials/error/self - dialing the local node's id
• p2p/dials/error/useless - dialing a peer that doesn't share an capabilities with the local node
• p2p/dials/error/id/unexpected - dialed peer repsoned with different id than expected
• p2p/dials/error/rlpx/enc - error negotiating the rlpx encryption during dial
• p2p/dials/error/rlpx/proto - error during rlpx protocol handshake

Example of new metrics under prometheus format:

p2p_dials 8

p2p_dials_error_connection 8

p2p_dials_error_id_unexpected 0

p2p_dials_error_known 0

p2p_dials_error_rlpx_enc 0

p2p_dials_error_rlpx_proto 0

p2p_dials_error_saturated 0

p2p_dials_error_self 0

p2p_dials_error_useless 0

p2p_dials_success 0

p2p_egress 8504

p2p_egress_eth_63_0x00 292

p2p_egress_eth_63_0x00_packets 4

p2p_egress_eth_63_0x02 2040

p2p_egress_eth_63_0x02_packets 12

p2p_egress_eth_63_0x03 62

p2p_egress_eth_63_0x03_packets 5

p2p_egress_eth_63_0x07 4142

p2p_egress_eth_63_0x07_packets 4

p2p_handle_eth_63_0x02_count 12

p2p_handle_eth_63_0x02 {quantile="0.5"} 467
p2p_handle_eth_63_0x02 {quantile="0.75"} 997.75
p2p_handle_eth_63_0x02 {quantile="0.95"} 1896
p2p_handle_eth_63_0x02 {quantile="0.99"} 1896
p2p_handle_eth_63_0x02 {quantile="0.999"} 1896
p2p_handle_eth_63_0x02 {quantile="0.9999"} 1896

p2p_handle_eth_63_0x04_count 5

p2p_handle_eth_63_0x04 {quantile="0.5"} 29
p2p_handle_eth_63_0x04 {quantile="0.75"} 727.5
p2p_handle_eth_63_0x04 {quantile="0.95"} 1340
p2p_handle_eth_63_0x04 {quantile="0.99"} 1340
p2p_handle_eth_63_0x04 {quantile="0.999"} 1340
p2p_handle_eth_63_0x04 {quantile="0.9999"} 1340

p2p_handle_eth_63_0x07_count 7

p2p_handle_eth_63_0x07 {quantile="0.5"} 105
p2p_handle_eth_63_0x07 {quantile="0.75"} 492
p2p_handle_eth_63_0x07 {quantile="0.95"} 1939
p2p_handle_eth_63_0x07 {quantile="0.99"} 1939
p2p_handle_eth_63_0x07 {quantile="0.999"} 1939
p2p_handle_eth_63_0x07 {quantile="0.9999"} 1939

p2p_ingress 11089

p2p_ingress_eth_63_0x00 292

p2p_ingress_eth_63_0x00_packets 4

p2p_ingress_eth_63_0x02 2040

p2p_ingress_eth_63_0x02_packets 12

p2p_ingress_eth_63_0x04 2490

p2p_ingress_eth_63_0x04_packets 5

p2p_ingress_eth_63_0x07 6321

p2p_ingress_eth_63_0x07_packets 7

p2p_peers 4

p2p_serves 4

p2p_serves_success 4

References:

• p2p: measure subprotocol bandwidth usage ethereum/go-ethereum#20133
• p2p, p2p/discover: add dial metrics ethereum/go-ethereum#27621
• p2p/discover: add traffic metrics ethereum/go-ethereum#27008