vulkan: Reserve 4 images in the swapchain by default

With the previous approach we would spend most of the time waiting for
the swapchain to be filled again because it seems the compositor takes
care of 2 images at once from time to time.

This is not visible in profiles because waiting for a frame is a
read/poll/whatever operation that does not take CPU. It's only
noticeable because the app becomes less responsive.

diff --git a/gdk/gdkvulkancontext.c b/gdk/gdkvulkancontext.c
index ba2c44b5c91775cccd4913cdce18345a839e0256..b9c24dcbe8f5e5f2c1a0af4300e8526a727b40df 100644 (file)
--- a/gdk/gdkvulkancontext.c
+++ b/gdk/gdkvulkancontext.c
@@ -305,7 +305,7 @@ gdk_vulkan_context_check_swapchain (GdkVulkanContext  *context,
                                                 .pNext = NULL,
                                                 .flags = 0,
                                                 .surface = priv->surface,
-                                                .minImageCount = CLAMP (2,
+                                                .minImageCount = CLAMP (4,
                                                                         capabilities.minImageCount,
                                                                         capabilities.maxImageCount ? capabilities.maxImageCount : G_MAXUINT32),
                                                 .imageFormat = priv->image_format.format,