diff --git a/.vscode/cspell.dictionaries/shell.wordlist.txt b/.vscode/cspell.dictionaries/shell.wordlist.txt
index 8de66daef28..f6ebdfe517d 100644
--- a/.vscode/cspell.dictionaries/shell.wordlist.txt
+++ b/.vscode/cspell.dictionaries/shell.wordlist.txt
@@ -101,6 +101,7 @@ flamegraph
 flamegraphs
 gcov
 gmake
+gnuls
 grcov
 grep
 markdownlint
diff --git a/docs/src/performance.md b/docs/src/performance.md
index e51ae6b9511..975a743abe6 100644
--- a/docs/src/performance.md
+++ b/docs/src/performance.md
@@ -41,6 +41,8 @@ hyperfine \
   "{ls} -R ."
 ```
 
+For Ubuntu 25.10 and other distributions that use uutils by default, replace `bin/ls` with `bin/gnuls`. Also:
+
 ```
 # to improve the reproducibility of the results:
 taskset -c 0