From 0c0aab27e7ff9bba10e8710d55c3a7d629412803 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Otto=20Kr=C3=B6pke?= <mail@jkroepke.de>
Date: Fri, 9 Oct 2026 01:17:00 +0200
Subject: [PATCH] collector: add pprof labels to build and collection (#2562)
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Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>
---
 README.md                   |  3 +++
 pkg/collector/collect.go    | 11 +++++++----
 pkg/collector/collection.go | 12 ++++++++----
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index 6d6ccb5f..ebffe315 100644
--- a/README.md
+++ b/README.md
@@ -210,6 +210,9 @@ windows_exporter provides the following HTTP endpoints:
 * `/health`: Returns 200 OK when the exporter is running.
 * `/debug/pprof/`: Exposes the [pprof](https://golang.org/pkg/net/http/pprof/) endpoints. Only, if `--debug.enabled` is set.
 
+CPU and goroutine profiles include a `collector` label with the collector name, so profiles can be filtered by collector.
+Workers started during collector initialization inherit this label.
+
 ### Using [defaults] with `--collectors.enabled` argument
 
 Using `[defaults]`  with `--collectors.enabled` argument which gets expanded with all default collectors.
diff --git a/pkg/collector/collect.go b/pkg/collector/collect.go
index 3ff38953..efa2acf6 100644
--- a/pkg/collector/collect.go
+++ b/pkg/collector/collect.go
@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"log/slog"
 	"runtime/debug"
+	"runtime/pprof"
 	"sync"
 	"time"
 
@@ -85,10 +86,12 @@ func (c *Collection) collectAll(ctx context.Context, ch chan<- prometheus.Metric
 	// timeout handling is done in the execute function
 	for name, metricsCollector := range c.collectors {
 		wg.Go(func() {
-			collectorStatusCh <- collectorStatus{
-				name:       name,
-				statusCode: c.collectCollector(ctx, ch, logger, name, metricsCollector),
-			}
+			pprof.Do(ctx, pprof.Labels("collector", name), func(ctx context.Context) {
+				collectorStatusCh <- collectorStatus{
+					name:       name,
+					statusCode: c.collectCollector(ctx, ch, logger, name, metricsCollector),
+				}
+			})
 		})
 	}
 
diff --git a/pkg/collector/collection.go b/pkg/collector/collection.go
index 47c1a058..014ea20c 100644
--- a/pkg/collector/collection.go
+++ b/pkg/collector/collection.go
@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"log/slog"
 	"maps"
+	"runtime/pprof"
 	"slices"
 	gotime "time"
 
@@ -248,10 +249,13 @@ func (c *Collection) Build(ctx context.Context, logger *slog.Logger) error {
 		state := c.state.collector(name)
 
 		go func() {
-			resultCh <- buildResult{
-				name: collector.GetName(),
-				err:  state.build(ctx, logger, miSession, collector),
-			}
+			// Workers started by Build inherit the collector's profiling label.
+			pprof.Do(ctx, pprof.Labels("collector", name), func(ctx context.Context) {
+				resultCh <- buildResult{
+					name: collector.GetName(),
+					err:  state.build(ctx, logger, miSession, collector),
+				}
+			})
 		}()
 	}