From 9f9ce631a2ff44ebcb87b0b1390a21b13665db43 Mon Sep 17 00:00:00 2001
From: Dmitry Gutov <dgutov@yandex.ru>
Date: Mon, 6 Jul 2020 03:50:59 +0300
Subject: [PATCH] ; Add a note about a bottleneck

---
 lisp/progmodes/project.el | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index 08798d86f8e..188236427da 100644
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -396,6 +396,8 @@ backend implementation of `project-external-roots'.")
        (setq files
              (mapcar
               (lambda (file) (concat default-directory file))
+              ;; XXX: With large enough project, split-string becomes
+              ;; one of the bottlenecks.
               (split-string
                (apply #'vc-git--run-command-string nil "ls-files" args)
                "\0" t)))
-- 
2.39.5