How to interpret "processed_call_count" from RPC metric json

Using https://1.1.1.1/proxy/1.1.1.1:12000/rpcz

In collecting RPC connection stats, my data looks like this:

{
“inbound_connections”: [
{
“remote_ip”: “1.1.1.1:38718”,
“state”: “OPEN”,
“processed_call_count”: 17168
},
{
“remote_ip”: “1.1.1.2:43678”,
“state”: “OPEN”,
“processed_call_count”: 15661,
“connection_details”: {
“cql_connection_details”: {
“keyspace”: “keyspace1”
}
}
},
{
“remote_ip”: “1.1.1.3:37442”,
“state”: “OPEN”,
“processed_call_count”: 46869,
“connection_details”: {
“cql_connection_details”: {
“keyspace”: “keyspace2”
}
}
},
}

What is “processed_call_count” ? I assume that is remote procedure call count.
How often does it reset?
If my application makes a connection pool of 20 connections but leaves most unused, are the unused connection generating processed_call_counts? Like a keep alive.

The processed call counts are pretty useful because it gives an indication of active rpc calls and this can influence queue pressure.

The unused connections won’t have increasing processed_call_count.