From f53e7c147b48b4a5b81af6dac606f971c8179390 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 22 Jan 2026 18:59:58 +0000
Subject: [PATCH] perf: use XFlush instead of XSync in drw_map

---
 .jules/bolt.md | 3 +++
 drw.c          | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 00000000..dd1c6a84
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,3 @@
+## 2024-05-23 - XSync vs XFlush in Drawing Paths
+**Learning:** Found `XSync` being used in `drw_map`, causing blocking round-trips to the X server for every buffer swap. This defeats the purpose of double buffering and significantly reduces rendering throughput.
+**Action:** Replace `XSync` with `XFlush` in pure drawing functions. Only use `XSync` when synchronization or error handling is explicitly required.
diff --git a/drw.c b/drw.c
index 7e99a386..e3f9501b 100644
--- a/drw.c
+++ b/drw.c
@@ -494,7 +494,7 @@ void drw_map(Drw *drw, Window win, int x, int y, unsigned int w,
     }
 
     XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
-    XSync(drw->dpy, False);
+    XFlush(drw->dpy);
 }
 
 unsigned int drw_fontset_getwidth(Drw *drw, const char *text) {