gl: Tune the default VBO size to reduce overhead on embedded devices

Henry Song found that the 256k buffers were disadvantageous on his
embedded hardware. As there is no obvious right value for the default
VBO size, we can tune for the more obvious constraints.

Based on a patch by Henry Song <henry.song@samsung.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/cairo-gl-private.h b/src/cairo-gl-private.h
index d6b0554cc..7c97c49a6 100644
--- a/src/cairo-gl-private.h
+++ b/src/cairo-gl-private.h
@@ -91,8 +91,10 @@
  * Random number that is hopefully big enough to not cause many cache evictions. */
 #define CAIRO_GL_MAX_SHADERS_PER_CONTEXT 64
 
-/* VBO size that we allocate, smaller size means we gotta flush more often */
-#define CAIRO_GL_VBO_SIZE (256*1024)
+/* VBO size that we allocate, smaller size means we gotta flush more often,
+ * but larger means hogging more memory and can cause trouble for drivers
+ * (especially on embedded devices). */
+#define CAIRO_GL_VBO_SIZE (16*1024)
 
 typedef struct _cairo_gl_surface cairo_gl_surface_t;