Merge pull request #724 from ipfs:refine-buckets

fix(routing/http/server): adjust bucket sizes for http metrics

CHANGELOG.md

@@ -16,12 +16,12 @@ The following emojis are used to highlight certain changes:
 
 ### Added
 
-- `routing/http/server`: added Prometheus instrumentation to http delegated routing endpoints.
-- `routing/http/server`: added configurable routing timeout (`DefaultRoutingTimeout` being 30s) to prevent indefinite hangs during content/peer routing. Set custom duration via `WithRoutingTimeout`.
+- `routing/http/server`: added built-in Prometheus instrumentation to http delegated `/routing/v1/` endpoints, with custom buckets for response size and duration to match real world data observed at [the `delegated-ipfs.dev` instance](https://docs.ipfs.tech/concepts/public-utilities/#delegated-routing). [#718](https://github.com/ipfs/boxo/pull/718) [#724](https://github.com/ipfs/boxo/pull/724)
+- `routing/http/server`: added configurable routing timeout (`DefaultRoutingTimeout` being 30s) to prevent indefinite hangs during content/peer routing. Set custom duration via `WithRoutingTimeout`. [#720](https://github.com/ipfs/boxo/pull/720)
 
 ### Changed
 
-- No longer using `github.com/jbenet/goprocess` to avoid requiring in dependents.
+- No longer using `github.com/jbenet/goprocess` to avoid requiring in dependents. [#710](https://github.com/ipfs/boxo/pull/710)
 
 ### Removed
 

routing/http/server/server.go

@@ -158,9 +158,9 @@ func Handler(svc ContentRouter, opts ...Option) http.Handler {
 	// Create middleware with prometheus recorder
 	mdlw := middleware.New(middleware.Config{
 		Recorder: metrics.NewRecorder(metrics.Config{
-			Registry: server.promRegistry,
-			Prefix:   "delegated_routing_server",
-
+			Registry:        server.promRegistry,
+			Prefix:          "delegated_routing_server",
+			SizeBuckets:     prometheus.ExponentialBuckets(100, 4, 8), // [100 400 1600 6400 25600 102400 409600 1.6384e+06]
 			DurationBuckets: []float64{0.1, 0.5, 1, 2, 5, 8, 10, 20, 30},
 		}),
 	})