Add more common storage metrics (#1722)

- Enabled process exporter for storage services
- Changed zenith_proxy prefix to just proxy
- Removed old `monitoring` directory
- Removed common prefix for metrics, now our common metrics have `libmetrics_` prefix, for example `libmetrics_serve_metrics_count`
- Added `test_metrics_normal_work`

proxy/src/main.rs

@@ -38,7 +38,6 @@ async fn flatten_err(
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
-    metrics::set_common_metrics_prefix("zenith_proxy");
     let arg_matches = App::new("Neon proxy/router")
         .version(GIT_VERSION)
         .arg(

proxy/src/proxy.rs

@@ -5,7 +5,7 @@ use crate::stream::{MetricsStream, PqStream, Stream};
 use anyhow::{bail, Context};
 use futures::TryFutureExt;
 use lazy_static::lazy_static;
-use metrics::{new_common_metric_name, register_int_counter, IntCounter};
+use metrics::{register_int_counter, IntCounter};
 use std::sync::Arc;
 use tokio::io::{AsyncRead, AsyncWrite};
 use utils::pq_proto::{BeMessage as Be, *};
@@ -15,17 +15,17 @@ const ERR_PROTO_VIOLATION: &str = "protocol violation";
 
 lazy_static! {
     static ref NUM_CONNECTIONS_ACCEPTED_COUNTER: IntCounter = register_int_counter!(
-        new_common_metric_name("num_connections_accepted"),
+        "proxy_accepted_connections",
         "Number of TCP client connections accepted."
     )
     .unwrap();
     static ref NUM_CONNECTIONS_CLOSED_COUNTER: IntCounter = register_int_counter!(
-        new_common_metric_name("num_connections_closed"),
+        "proxy_closed_connections",
         "Number of TCP client connections closed."
     )
     .unwrap();
     static ref NUM_BYTES_PROXIED_COUNTER: IntCounter = register_int_counter!(
-        new_common_metric_name("num_bytes_proxied"),
+        "proxy_io_bytes",
         "Number of bytes sent/received between any client and backend."
     )
     .unwrap();