diff --git a/hw/kdrive/ephyr/ephyr_glamor_glx.c b/hw/kdrive/ephyr/ephyr_glamor_glx.c
index 2f219141e..007123c31 100644
--- a/hw/kdrive/ephyr/ephyr_glamor_glx.c
+++ b/hw/kdrive/ephyr/ephyr_glamor_glx.c
@@ -57,6 +57,7 @@ static Display *dpy;
 static XVisualInfo *visual_info;
 static GLXFBConfig fb_config;
 Bool ephyr_glamor_gles2;
+Bool ephyr_glamor_skip_present;
 /** @} */
 
 /**
@@ -220,6 +221,13 @@ ephyr_glamor_damage_redisplay(struct ephyr_glamor *glamor,
 {
     GLint old_vao;
 
+    /* Skip presenting the output in this mode.  Presentation is
+     * expensive, and if we're just running the X Test suite headless,
+     * nobody's watching.
+     */
+    if (ephyr_glamor_skip_present)
+        return;
+
     glXMakeCurrent(dpy, glamor->glx_win, glamor->ctx);
 
     if (glamor->vao) {
diff --git a/hw/kdrive/ephyr/ephyrinit.c b/hw/kdrive/ephyr/ephyrinit.c
index 149ea981e..7632c2643 100644
--- a/hw/kdrive/ephyr/ephyrinit.c
+++ b/hw/kdrive/ephyr/ephyrinit.c
@@ -36,7 +36,7 @@ extern Bool EphyrWantResize;
 extern Bool EphyrWantNoHostGrab;
 extern Bool kdHasPointer;
 extern Bool kdHasKbd;
-extern Bool ephyr_glamor, ephyr_glamor_gles2;
+extern Bool ephyr_glamor, ephyr_glamor_gles2, ephyr_glamor_skip_present;
 
 extern Bool ephyrNoXV;
 
@@ -148,6 +148,7 @@ ddxUseMsg(void)
 #ifdef GLAMOR
     ErrorF("-glamor              Enable 2D acceleration using glamor\n");
     ErrorF("-glamor_gles2        Enable 2D acceleration using glamor (with GLES2 only)\n");
+    ErrorF("-glamor-skip-present Skip presenting the output when using glamor (for internal testing optimization)\n");
 #endif
     ErrorF
         ("-fakexa              Simulate acceleration using software rendering\n");
@@ -288,6 +289,10 @@ ddxProcessArgument(int argc, char **argv, int i)
         ephyrFuncs.finiAccel = ephyr_glamor_fini;
         return 1;
     }
+    else if (!strcmp (argv[i], "-glamor-skip-present")) {
+        ephyr_glamor_skip_present = TRUE;
+        return 1;
+    }
 #endif
     else if (!strcmp(argv[i], "-fakexa")) {
         ephyrFuncs.initAccel = ephyrDrawInit;