From a37cef9ee66bb380882b5a6c29b815276859e35a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jakub=20Ber=C3=A1nek?= <berykubik@gmail.com>
Date: Thu, 27 Mar 2025 11:29:48 +0100
Subject: [PATCH] Add a note about interpreting job duration changes

---
 src/ci/citool/src/analysis.rs | 9 +++++++++
 src/ci/citool/src/utils.rs    | 1 -
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/ci/citool/src/analysis.rs b/src/ci/citool/src/analysis.rs
index fc18e438aab..2e1ede126dc 100644
--- a/src/ci/citool/src/analysis.rs
+++ b/src/ci/citool/src/analysis.rs
@@ -238,6 +238,15 @@ pub fn output_largest_duration_changes(job_metrics: &HashMap<JobName, JobMetrics
             entry.change
         );
     }
+
+    println!();
+    output_details("How to interpret the job duration changes?", || {
+        println!(
+            r#"Job durations can vary a lot, based on the actual runner instance
+that executed the job, system noise, invalidated caches, etc. The table above is provided
+mostly for t-infra members, for simpler debugging of potential CI slow-downs."#
+        );
+    });
 }
 
 #[derive(Default)]
diff --git a/src/ci/citool/src/utils.rs b/src/ci/citool/src/utils.rs
index b9b1bf4d455..a4c6ff85ef7 100644
--- a/src/ci/citool/src/utils.rs
+++ b/src/ci/citool/src/utils.rs
@@ -23,7 +23,6 @@ where
     println!(
         r"<details>
 <summary>{summary}</summary>
-
 "
     );
     func();