pipeline: inputs: process-exporter-metrics: Add threading info

Signed-off-by: Alexa Kreizinger <alexakreizinger@gmail.com>

Author: alexakreizinger

pipeline/inputs/process-exporter-metrics.md

@@ -42,6 +42,10 @@ macOS does not have the `proc` filesystem so this plugin will not work for it.
 | thread\_wchan     | Exposes thread\_wchan from `/proc`.                |
 | thread            | Exposes thread statistics from `/proc`.            |
 
+## Threading
+
+This input always runs in its own [thread](../../administration/multithreading.md#inputs).
+
 ## Getting Started
 
 ### Simple Configuration File
@@ -83,7 +87,7 @@ curl http://127.0.0.1:2021/metrics
 ### Container to Collect Host Metrics
 
 When deploying Fluent Bit in a container you will need to specify additional settings to ensure that Fluent Bit has access to the process details.
-The following `docker` command deploys Fluent Bit with a specific mount path for `procfs` and settings enabled to ensure that Fluent Bit can collect from the host. 
+The following `docker` command deploys Fluent Bit with a specific mount path for `procfs` and settings enabled to ensure that Fluent Bit can collect from the host.
 These are then exposed over port 2021.
 
 ```