Startup of a simple Game on MacOS takes an excessive amount of time

[jazzay]

Now that we can publish a build for MacOS. When running that build on my MBP 2015 (decent video hardware) it takes ~7 mins to startup. Way longer than on windows which is closer to 10 secs.

The console output looks like so. Indicating possibly that the shader compiles for Molten is what's taking so long:

[mvk-info] MoltenVK version 1.0.30. Vulkan version 1.0.95.
	The following Vulkan extensions are supported:
		VK_KHR_16bit_storage v1
		VK_KHR_8bit_storage v1
		VK_KHR_bind_memory2 v1
		VK_KHR_dedicated_allocation v3
		VK_KHR_descriptor_update_template v1
		VK_KHR_get_memory_requirements2 v1
		VK_KHR_get_physical_device_properties2 v1
		VK_KHR_image_format_list v1
		VK_KHR_maintenance1 v2
		VK_KHR_maintenance2 v1
		VK_KHR_maintenance3 v1
		VK_KHR_push_descriptor v2
		VK_KHR_relaxed_block_layout v1
		VK_KHR_sampler_mirror_clamp_to_edge v1
		VK_KHR_shader_draw_parameters v1
		VK_KHR_shader_float16_int8 v1
		VK_KHR_storage_buffer_storage_class v1
		VK_KHR_surface v25
		VK_KHR_swapchain v70
		VK_KHR_swapchain_mutable_format v1
		VK_EXT_shader_viewport_index_layer v1
		VK_EXT_vertex_attribute_divisor v3
		VK_MVK_macos_surface v2
		VK_MVK_moltenvk v15
		VK_AMD_negative_viewport_height v1
[mvk-info] GPU device:
		model: AMD Radeon R9 M370X
		type: Discrete
		vendorID: 0x1002
		deviceID: 0x6821
		pipelineCacheUUID: 00000000-0000-0000-0000-27130000272E
	supports Metal Shading Language version 2.1 and the following Metal Feature Sets:
		macOS GPU Family 2 v1
		macOS GPU Family 1 v4
		macOS GPU Family 1 v3
		macOS GPU Family 1 v2
		macOS GPU Family 1 v1
		macOS Read-Write Texture Tier 2
[mvk-info] GPU device:
		model: Intel Iris Pro Graphics
		type: Integrated
		vendorID: 0x8086
		deviceID: 0x0d26
		pipelineCacheUUID: 00000000-0000-0000-0000-27130000272E
	supports Metal Shading Language version 2.1 and the following Metal Feature Sets:
		macOS GPU Family 1 v4
		macOS GPU Family 1 v3
		macOS GPU Family 1 v2
		macOS GPU Family 1 v1
[mvk-info] Created VkInstance with the following Vulkan extensions enabled:
		VK_KHR_surface v25
[mvk-info] Created VkDevice to run on GPU AMD Radeon R9 M370X with the following Vulkan extensions enabled:
		VK_KHR_swapchain v70
[mvk-info] Created 2 swapchain images with initial size (1280, 720).
[mvk-info] Created 2 swapchain images with initial size (1280, 720).
[mvk-info] Shader library compilation succeeded with warnings (code 4):

Compilation succeeded with: 

program_source:803:22: warning: variable 'lightVectorNorm' is uninitialized when used here
    float3 param_2 = lightVectorNorm;
                     ^~~~~~~~~~~~~~~
program_source:802:5: note: variable 'lightVectorNorm' is declared here
    float3 lightVectorNorm;
    ^
program_source:935:22: warning: variable 'lightVectorNorm' is uninitialized when used here
    float3 param_4 = lightVectorNorm;
                     ^~~~~~~~~~~~~~~
program_source:934:5: note: variable 'lightVectorNorm' is declared here
    float3 lightVectorNorm;
    ^

[jazzay]

Note i get to these lines immediately after launch:

[mvk-info] Created 2 swapchain images with initial size (1280, 720).
[mvk-info] Created 2 swapchain images with initial size (1280, 720).

Shader compilation succeed arrives 7 mins later.

[xen2]

Tried only with a New Game and it didn't take that much time.
Did you try with a more complex sample?

Anyway, yes, there is a few things that will be done to drastically improve shader compilation perf (not only for macOS but every platform):

• Shader System Rewrite Epic #14 is probably what will have the most meaningful impact.
  This is quite some work. Ideally it would be great if somebody would step up and take it over.
• Once Shader System Rewrite Epic #14 is there, on top of having much faster XKSL => SPIR-V, we could avoid extra conversion steps by going almost directly from XKSL => SPIR-V => MSL in memory, and sending MSL directly to MoltenVK (they have some extensions for that).

[jazzay]

I used the basic New Game template that creates a simple sphere with lighting, shadows.