From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 10 Jul 2026 14:32:14 +0000 (+0000)
Subject: graphs: knot-resolver: Add a cache performance graph
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3101d67f62beb0cc4cf48da21d2d17ef9d0a5f4;p=telemetry.git

graphs: knot-resolver: Add a cache performance graph

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/daemon/graphs.c b/src/daemon/graphs.c
index 5f25ee4..5d8e6b1 100644
--- a/src/daemon/graphs.c
+++ b/src/daemon/graphs.c
@@ -95,6 +95,7 @@ static const td_graph_impl* graph_impls[] = {
 
 	// Knot Resolver
 	&knot_resolver_queries_graph,
+	&knot_resolver_cache_graph,
 
 	// Unbound
 	&unbound_cache_performance_graph,
diff --git a/src/daemon/graphs/knot-resolver.c b/src/daemon/graphs/knot-resolver.c
index 7c71066..aab50bb 100644
--- a/src/daemon/graphs/knot-resolver.c
+++ b/src/daemon/graphs/knot-resolver.c
@@ -28,6 +28,8 @@ static int knot_resolver_can_render(td_ctx* ctx, td_graph* graph,
 	return td_graph_requires_source(graph, "knot-resolver", NULL);
 }
 
+// Queries
+
 static int knot_resolver_queries_title(td_ctx* ctx, td_graph* graph,
 		const char* object, char* title, size_t length) {
 	return __td_string_set(title, length, _("DNS Queries"));
@@ -63,3 +65,60 @@ const td_graph_impl knot_resolver_queries_graph = {
 	.lower_limit = 0,
 	.upper_limit = LONG_MAX,
 };
+
+// Cache
+
+static int knot_resolver_cache_title(td_ctx* ctx, td_graph* graph,
+		const char* object, char* title, size_t length) {
+	return __td_string_set(title, length, _("Cache Performance"));
+}
+
+static int knot_resolver_cache_render(td_ctx* ctx, td_graph* graph,
+		const td_graph_render_options* options, td_args* args, const char* object) {
+	int r;
+
+	// Load all sources
+	r = td_graph_load_source(graph, args, "knot-resolver", NULL);
+	if (r < 0)
+		return r;
+
+	// Compute cache misses
+	COMPUTE_DIFFERENCE(args, "answer_missed", NULL,
+		"answer_total", NULL, "answer_cached", NULL);
+
+	// Header
+	PRINT_HEADER4(args, _("Current"), _("Average"), _("Minimum"), _("Maximum"));
+
+	// Show the total queries
+	PRINT_LABEL(args, _("Total"));
+	PRINT_CAMM(args, "answer_total", NULL, QPS, QPS_UNIT);
+
+	PRINT_EMPTY_LINE(args);
+
+	// Draw the stacked background first
+	DRAW_AREA_BACKGROUND(args, "answer_cached", NULL, COLOR_CACHE_HIT, 0);
+	DRAW_AREA_BACKGROUND(args, "answer_missed", NULL, COLOR_CACHE_MISS, STACKED);
+
+	// Draw the area outlines afterwards
+	DRAW_AREA_OUTLINE_WITH_LABEL(args, "answer_cached", NULL,
+		COLOR_CACHE_HIT, 0, _("Cache Hits"));
+	PRINT_CAMM(args, "answer_cached", NULL, QPS, QPS_UNIT);
+
+	DRAW_AREA_OUTLINE_WITH_LABEL(args, "answer_missed", NULL,
+		COLOR_CACHE_MISS, STACKED, _("Cache Miss"));
+	PRINT_CAMM(args, "answer_missed", NULL, QPS, QPS_UNIT);
+
+	return 0;
+}
+
+const td_graph_impl knot_resolver_cache_graph = {
+	.name        = "KnotResolverCache",
+	.can_render  = knot_resolver_can_render,
+	.render      = knot_resolver_cache_render,
+	.title       = knot_resolver_cache_title,
+	.vlabel      = td_graph_vlabel_qps,
+
+	// Limits
+	.lower_limit = 0,
+	.upper_limit = LONG_MAX,
+};
diff --git a/src/daemon/graphs/knot-resolver.h b/src/daemon/graphs/knot-resolver.h
index 1354802..15cb165 100644
--- a/src/daemon/graphs/knot-resolver.h
+++ b/src/daemon/graphs/knot-resolver.h
@@ -24,5 +24,6 @@
 #include "../graph.h"
 
 extern const td_graph_impl knot_resolver_queries_graph;
+extern const td_graph_impl knot_resolver_cache_graph;
 
 #endif /* TELEMETRY_GRAPH_KNOT_RESOLVER_H */