lstalmir · lstalmir · May 4, 2026
diff --git a/Docs/options.rst b/Docs/options.rst
@@ -199,3 +199,9 @@ This section describes in detail all available configuration options exposed by
 .. confval:: ref_metrics
     :type: path
     :default: empty
+
+.. confval:: synchronize_queues
+    :type: bool
+    :default: false
+
+    When enabled, the layer will insert synchronization primitives to ensure that any work is executed without overlap with the other queues. This can help to reduce variability in performance measurements caused by asynchronous GPU execution. However, it will also significantly impact the overall performance of the application, so it is recommended to use this option only for specific use cases where accurate timing of individual queues is required.
diff --git a/VkLayer_profiler_layer/VkLayer_profiler_layer.json.in b/VkLayer_profiler_layer/VkLayer_profiler_layer.json.in
@@ -106,7 +106,10 @@
                             "dependence": {
                                 "mode": "ALL",
                                 "settings": [
-                                    { "key": "output", "value": "trace" }
+                                    {
+                                        "key": "output",
+                                        "value": "trace"
+                                    }
                                 ]
                             }
                         }
@@ -167,7 +170,10 @@
                             "dependence": {
                                 "mode": "ALL",
                                 "settings": [
-                                    { "key": "enable_performance_query_ext", "value": "intel" }
+                                    {
+                                        "key": "enable_performance_query_ext",
+                                        "value": "intel"
+                                    }
                                 ]
                             }
                         },
@@ -181,8 +187,14 @@
                             "dependence": {
                                 "mode": "ALL",
                                 "settings": [
-                                    { "key": "enable_performance_query_ext", "value": "intel" },
-                                    { "key": "performance_query_mode", "value": "stream" }
+                                    {
+                                        "key": "enable_performance_query_ext",
+                                        "value": "intel"
+                                    },
+                                    {
+                                        "key": "performance_query_mode",
+                                        "value": "stream"
+                                    }
                                 ]
                             }
                         },
@@ -196,7 +208,10 @@
                             "dependence": {
                                 "mode": "ALL",
                                 "settings": [
-                                    { "key": "enable_performance_query_ext", "value": "intel" }
+                                    {
+                                        "key": "enable_performance_query_ext",
+                                        "value": "intel"
+                                    }
                                 ]
                             }
                         }
@@ -329,6 +344,14 @@
                     "env": "VKPROF_ref_metrics",
                     "type": "LOAD_FILE",
                     "default": ""
+                },
+                {
+                    "key": "synchronize_queues",
+                    "label": "Synchronize queues",
+                    "description": "Synchronize all command buffer submissions to prevent concurrent execution on multiple queues during measurements.",
+                    "env": "VKPROF_synchronize_queues",
+                    "type": "BOOL",
+                    "default": false
                 }
             ]
         }

diff --git a/VkLayer_profiler_layer/profiler/profiler.cpp b/VkLayer_profiler_layer/profiler/profiler.cpp
@@ -647,6 +647,24 @@ namespace Profiler
 
     /***********************************************************************************\
 
+    Function:
+        SetSynchronizeQueues
+
+    Description:
+        Enable or disable synchronization of queue submissions.
+
+    \***********************************************************************************/
+    VkResult DeviceProfiler::SetSynchronizeQueues( bool synchronize )
+    {
+        std::scoped_lock lk( m_SubmitMutex );
+
+        m_Config.m_SynchronizeQueues = synchronize;
+
+        return VK_SUCCESS;
+    }
+
+    /***********************************************************************************\
+
     \***********************************************************************************/
     std::shared_ptr<DeviceProfilerFrameData> DeviceProfiler::GetData()
     {
@@ -1337,6 +1355,12 @@ namespace Profiler
     \***********************************************************************************/
     void DeviceProfiler::PreSubmitCommandBuffers( VkQueue queue )
     {
+        // Synchronize access to the queue if requested.
+        if( m_Config.m_SynchronizeQueues )
+        {
+            m_SubmitMutex.lock();
+        }
+
         // Configure the queue for performance counters collection, if needed.
         if( m_pPerformanceCounters )
         {
@@ -1486,8 +1510,20 @@ namespace Profiler
             }
         }
 
+        // If synchronization between queues is enabled, wait with the mutex locked to ensure it is completed before the next submission.
+        if( m_Config.m_SynchronizeQueues )
+        {
+            m_pDevice->Callbacks.QueueWaitIdle( queue );
+        }
+
         // Get data captured during the last frame
         ResolveFrameData( tip );
+
+        // Release the lock acquired in PreSubmitCommandBuffers.
+        if( m_Config.m_SynchronizeQueues )
+        {
+            m_SubmitMutex.unlock();
+        }
     }
 
     /***********************************************************************************\

diff --git a/VkLayer_profiler_layer/profiler/profiler.h b/VkLayer_profiler_layer/profiler/profiler.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2019-2025 Lukasz Stalmirski
+// Copyright (c) 2019-2026 Lukasz Stalmirski
 // 
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -78,6 +78,7 @@ namespace Profiler
         VkResult SetFrameDelimiter( VkProfilerFrameDelimiterEXT );
         VkResult SetDataBufferSize( uint32_t );
         VkResult SetMinDataBufferSize( uint32_t );
+        VkResult SetSynchronizeQueues( bool );
         std::shared_ptr<DeviceProfilerFrameData> GetData();
 
         ProfilerCommandBuffer& GetCommandBuffer( VkCommandBuffer commandBuffer );
@@ -200,6 +201,8 @@ namespace Profiler
         DeviceProfilerSynchronization m_Synchronization;
         DeviceProfilerSynchronizationTimestamps m_SynchronizationTimestamps;
 
+        std::mutex              m_SubmitMutex;
+
         // Whether VK_KHR_pipeline_executable_properties is available for the profiled device.
         // In such case the internal representations of pipelines may be inspected to give more insight on potential performance issues.
         bool                    m_PipelineExecutablePropertiesEnabled;

diff --git a/VkLayer_profiler_layer/profiler/profiler_frontend.h b/VkLayer_profiler_layer/profiler/profiler_frontend.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2025 Lukasz Stalmirski
+// Copyright (c) 2025-2026 Lukasz Stalmirski
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -82,6 +82,8 @@ namespace Profiler
         virtual VkProfilerModeEXT GetProfilerSamplingMode() = 0;
         virtual VkResult SetProfilerSamplingMode( VkProfilerModeEXT mode ) = 0;
 
+        virtual VkResult SetSynchronizeQueues( bool synchronize ) = 0;
+
         virtual std::string GetObjectName( const struct VkObject& object ) = 0;
         virtual void SetObjectName( const struct VkObject& object, const std::string& name ) = 0;
 

diff --git a/VkLayer_profiler_layer/profiler_layer_objects/profiler_layer_frontend.cpp b/VkLayer_profiler_layer/profiler_layer_objects/profiler_layer_frontend.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2025 Lukasz Stalmirski
+// Copyright (c) 2025-2026 Lukasz Stalmirski
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -528,6 +528,20 @@ namespace Profiler
 
     /***********************************************************************************\
 
+    Function:
+        SetSynchronizeQueues
+
+    Description:
+        Enable or disable synchronization of command buffer submissions.
+
+    \***********************************************************************************/
+    VkResult DeviceProfilerLayerFrontend::SetSynchronizeQueues( bool synchronize )
+    {
+        return m_pProfiler->SetSynchronizeQueues( synchronize );
+    }
+
+    /***********************************************************************************\
+
     Function:
         GetObjectName
 

diff --git a/VkLayer_profiler_layer/profiler_layer_objects/profiler_layer_frontend.h b/VkLayer_profiler_layer/profiler_layer_objects/profiler_layer_frontend.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2025 Lukasz Stalmirski
+// Copyright (c) 2025-2026 Lukasz Stalmirski
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -82,6 +82,8 @@ namespace Profiler
         VkProfilerModeEXT GetProfilerSamplingMode() final;
         VkResult SetProfilerSamplingMode( VkProfilerModeEXT mode ) final;
 
+        VkResult SetSynchronizeQueues( bool synchronizeQueues ) final;
+
         std::string GetObjectName( const VkObject& object ) final;
         void SetObjectName( const VkObject& object, const std::string& name ) final;
 

diff --git a/VkLayer_profiler_layer/profiler_overlay/lang/en_us.h b/VkLayer_profiler_layer/profiler_overlay/lang/en_us.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2019-2021 Lukasz Stalmirski
+// Copyright (c) 2019-2026 Lukasz Stalmirski
 // 
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -176,6 +176,7 @@ namespace Profiler
         inline static constexpr char ShowDebugLabels[] = "Show debug labels";
         inline static constexpr char ShowShaderCapabilities[] = "Show shader capabilities";
         inline static constexpr char ShowEntryPoints[] = "Show entry points";
+        inline static constexpr char SynchronizeQueues[] = "Synchronize queues";
         inline static constexpr char TimeUnit[] = "Time unit";
 
         inline static constexpr char Milliseconds[] = "ms";

diff --git a/VkLayer_profiler_layer/profiler_overlay/profiler_overlay.cpp b/VkLayer_profiler_layer/profiler_overlay/profiler_overlay.cpp
@@ -554,6 +554,8 @@ namespace Profiler
             }
 
             SetMaxFrameCount( std::max( config.m_FrameCount, 0 ) );
+
+            m_SynchronizeQueues = config.m_SynchronizeQueues;
         }
 
         // Don't leave object in partly-initialized state if something went wrong
@@ -644,6 +646,7 @@ namespace Profiler
         m_ShowAllTopPipelines = false;
         m_ShowActiveFrame = false;
         m_ShowEntryPoints = false;
+        m_SynchronizeQueues = false;
 
         m_SetLastMainWindowPos = false;
 
@@ -6494,6 +6497,12 @@ namespace Profiler
             SetMaxFrameCount( std::max<uint32_t>( 0, maxFrameCount ) );
         }
 
+        // Control queue synchronization
+        if( ImGui::Checkbox( Lang::SynchronizeQueues, &m_SynchronizeQueues ) )
+        {
+            m_Frontend.SetSynchronizeQueues( m_SynchronizeQueues );
+        }
+
         // Select sampling mode (constant in runtime for now)
         ImGui::BeginDisabled();
         {

diff --git a/VkLayer_profiler_layer/profiler_overlay/profiler_overlay.h b/VkLayer_profiler_layer/profiler_overlay/profiler_overlay.h
@@ -170,6 +170,7 @@ namespace Profiler
         bool m_ShowAllTopPipelines;
         bool m_ShowActiveFrame;
         bool m_ShowEntryPoints;
+        bool m_SynchronizeQueues;
 
         bool GetShowActiveFrame() const;
         const FrameDataList& GetActiveFramesList() const;