Minimal invasive fix for the memory leak in the performance sample multi_draw_indirect. (#1444)

Author: asuessenbach

framework/core/command_pool.h

@@ -68,7 +68,7 @@ class CommandPool : private vkb::core::CommandPoolBase
 	            uint32_t                                  queue_family_index,
 	            vkb::rendering::RenderFrame<bindingType> *render_frame = nullptr,
 	            size_t                                    thread_index = 0,
-	            vkb::CommandBufferResetMode               reset_mode   = vkb::CommandBufferResetMode::ResetPool);
+	            vkb::CommandBufferResetMode               reset_mode   = vkb::CommandBufferResetMode::ResetIndividually);
 	CommandPool(CommandPool<bindingType> const &)            = delete;
 	CommandPool(CommandPool<bindingType> &&other)            = default;
 	CommandPool &operator=(CommandPool<bindingType> const &) = delete;

samples/performance/multi_draw_indirect/multi_draw_indirect.cpp

@@ -198,13 +198,13 @@ void MultiDrawIndirect::on_update_ui_overlay(vkb::Drawer &drawer)
 			assert(!!indirect_call_buffer && !!cpu_staging_buffer && indirect_call_buffer->get_size() == cpu_staging_buffer->get_size());
 			assert(cpu_commands.size() * sizeof(cpu_commands[0]) == cpu_staging_buffer->get_size());
 
-			auto cmd = get_device().get_command_pool().request_command_buffer();
-			cmd->begin(VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT);
-			cmd->copy_buffer(*indirect_call_buffer, *cpu_staging_buffer, cpu_staging_buffer->get_size());
-			cmd->end();
+			ui_overlay_command_buffer->reset(vkb::CommandBufferResetMode::ResetIndividually);
+			ui_overlay_command_buffer->begin(VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT);
+			ui_overlay_command_buffer->copy_buffer(*indirect_call_buffer, *cpu_staging_buffer, cpu_staging_buffer->get_size());
+			ui_overlay_command_buffer->end();
 
 			auto &queue = get_device().get_queue_by_flags(VK_QUEUE_COMPUTE_BIT, 0);
-			queue.submit(*cmd, get_device().get_fence_pool().request_fence());
+			queue.submit(*ui_overlay_command_buffer, get_device().get_fence_pool().request_fence());
 			get_device().get_fence_pool().wait();
 
 			memcpy(cpu_commands.data(), cpu_staging_buffer->get_data(), cpu_staging_buffer->get_size());
@@ -278,6 +278,8 @@ bool MultiDrawIndirect::prepare(const vkb::ApplicationOptions &options)
 		}
 	}
 
+	ui_overlay_command_buffer = get_device().get_command_pool().request_command_buffer();
+
 	create_samplers();
 	load_scene();
 	initialize_resources();

samples/performance/multi_draw_indirect/multi_draw_indirect.h

@@ -128,6 +128,8 @@ class MultiDrawIndirect : public ApiVulkanSample
 	const vkb::Queue                      *compute_queue{nullptr};
 	std::vector<uint32_t>                  queue_families;
 
+	std::shared_ptr<vkb::core::CommandBufferC> ui_overlay_command_buffer;
+
 	// CPU Draw Calls
 	void                                      cpu_cull();
 	std::vector<VkDrawIndexedIndirectCommand> cpu_commands;