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⚡ Bolt: Use XFlush instead of XSync in drw_map #180

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⚡ Bolt: Use XFlush instead of XSync in drw_map #180

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3 changes: 3 additions & 0 deletions .jules/bolt.md
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@@ -0,0 +1,3 @@
## 2026-01-23 - XSync vs XFlush in drw_map
**Learning:** In X11 window managers, using XSync in frequent drawing paths (like drw_map) causes blocking round-trips to the X server, significantly degrading performance.
**Action:** Use XFlush for drawing operations where synchronous confirmation is not required.
4 changes: 3 additions & 1 deletion drw.c
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Expand Up @@ -494,7 +494,9 @@ 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 is used here instead of XSync to avoid blocking round-trips
* during frequent drawing operations. */
XFlush(drw->dpy);
}

unsigned int drw_fontset_getwidth(Drw *drw, const char *text) {
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