From 536007a420c472e0d9c7481d42b1cb021817c0dd Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 16:39:37 -0700
Subject: [PATCH 01/11] [Impeller] one descriptor pool per frame.

---
 .../backend/vulkan/command_buffer_vk.cc       |  6 ++---
 .../backend/vulkan/command_buffer_vk.h        |  4 +--
 .../renderer/backend/vulkan/context_vk.cc     | 26 ++++++++++++++-----
 .../backend/vulkan/surface_context_vk.cc      |  2 +-
 .../backend/vulkan/tracked_objects_vk.cc      |  5 ++--
 .../backend/vulkan/tracked_objects_vk.h       |  3 ++-
 6 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/command_buffer_vk.cc b/impeller/renderer/backend/vulkan/command_buffer_vk.cc
index abe4971298c28..3d432f3576ee3 100644
--- a/impeller/renderer/backend/vulkan/command_buffer_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_buffer_vk.cc
@@ -22,12 +22,10 @@ namespace impeller {
 CommandBufferVK::CommandBufferVK(
     std::weak_ptr<const Context> context,
     std::weak_ptr<const DeviceHolderVK> device_holder,
-    std::shared_ptr<TrackedObjectsVK> tracked_objects,
-    std::shared_ptr<FenceWaiterVK> fence_waiter)
+    std::shared_ptr<TrackedObjectsVK> tracked_objects)
     : CommandBuffer(std::move(context)),
       device_holder_(std::move(device_holder)),
-      tracked_objects_(std::move(tracked_objects)),
-      fence_waiter_(std::move(fence_waiter)) {}
+      tracked_objects_(std::move(tracked_objects)) {}
 
 CommandBufferVK::~CommandBufferVK() = default;
 
diff --git a/impeller/renderer/backend/vulkan/command_buffer_vk.h b/impeller/renderer/backend/vulkan/command_buffer_vk.h
index 6a78787f1dce5..aee53db409a58 100644
--- a/impeller/renderer/backend/vulkan/command_buffer_vk.h
+++ b/impeller/renderer/backend/vulkan/command_buffer_vk.h
@@ -87,12 +87,10 @@ class CommandBufferVK final
 
   std::weak_ptr<const DeviceHolderVK> device_holder_;
   std::shared_ptr<TrackedObjectsVK> tracked_objects_;
-  std::shared_ptr<FenceWaiterVK> fence_waiter_;
 
   CommandBufferVK(std::weak_ptr<const Context> context,
                   std::weak_ptr<const DeviceHolderVK> device_holder,
-                  std::shared_ptr<TrackedObjectsVK> tracked_objects,
-                  std::shared_ptr<FenceWaiterVK> fence_waiter);
+                  std::shared_ptr<TrackedObjectsVK> tracked_objects);
 
   // |CommandBuffer|
   void SetLabel(std::string_view label) const override;
diff --git a/impeller/renderer/backend/vulkan/context_vk.cc b/impeller/renderer/backend/vulkan/context_vk.cc
index 222646983fb6f..46e582a49b7b1 100644
--- a/impeller/renderer/backend/vulkan/context_vk.cc
+++ b/impeller/renderer/backend/vulkan/context_vk.cc
@@ -6,6 +6,7 @@
 
 #include "fml/concurrent_message_loop.h"
 #include "impeller/renderer/backend/vulkan/command_queue_vk.h"
+#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/render_pass_builder_vk.h"
 #include "impeller/renderer/render_target.h"
 
@@ -489,15 +490,28 @@ std::shared_ptr<PipelineLibrary> ContextVK::GetPipelineLibrary() const {
   return pipeline_library_;
 }
 
+// DescriptorPool Lifecycle:
+// 1. End of frame will reset the descriptor pool (clearing this on a thread).
+//    There will still be references to the descriptor pool from the uncompleted
+//    command buffers.
+// 2. The last reference to the descriptor pool will be released from the fence
+//    waiter thread, which will schedule a task on the resource
+//    manager thread, which in turn will reset the command pool and make it
+//    available for reuse ("recycle").
+static thread_local std::shared_ptr<DescriptorPoolVK> tls_descriptor_pool;
+
 std::shared_ptr<CommandBuffer> ContextVK::CreateCommandBuffer() const {
   const auto& recycler = GetCommandPoolRecycler();
   auto tls_pool = recycler->Get();
   if (!tls_pool) {
     return nullptr;
   }
-
+  if (!tls_descriptor_pool) {
+    tls_descriptor_pool = std::make_shared<DescriptorPoolVK>(weak_from_this());
+  }
   auto tracked_objects = std::make_shared<TrackedObjectsVK>(
-      weak_from_this(), std::move(tls_pool), GetGPUTracer()->CreateGPUProbe());
+      weak_from_this(), std::move(tls_pool), tls_descriptor_pool,
+      GetGPUTracer()->CreateGPUProbe());
   auto queue = GetGraphicsQueue();
 
   if (!tracked_objects || !tracked_objects->IsValid() || !queue) {
@@ -516,10 +530,9 @@ std::shared_ptr<CommandBuffer> ContextVK::CreateCommandBuffer() const {
       tracked_objects->GetCommandBuffer());
 
   return std::shared_ptr<CommandBufferVK>(new CommandBufferVK(
-      shared_from_this(),          //
-      GetDeviceHolder(),           //
-      std::move(tracked_objects),  //
-      GetFenceWaiter()             //
+      shared_from_this(),         //
+      GetDeviceHolder(),          //
+      std::move(tracked_objects)  //
       ));
 }
 
@@ -631,6 +644,7 @@ void ContextVK::InitializeCommonlyUsedShadersIfNeeded() const {
 
 void ContextVK::DisposeThreadLocalCachedResources() {
   command_pool_recycler_->Dispose();
+  tls_descriptor_pool.reset();
 }
 
 const std::shared_ptr<YUVConversionLibraryVK>&
diff --git a/impeller/renderer/backend/vulkan/surface_context_vk.cc b/impeller/renderer/backend/vulkan/surface_context_vk.cc
index 912c74b03c056..b5ddd61a04e01 100644
--- a/impeller/renderer/backend/vulkan/surface_context_vk.cc
+++ b/impeller/renderer/backend/vulkan/surface_context_vk.cc
@@ -86,7 +86,7 @@ std::unique_ptr<Surface> SurfaceContextVK::AcquireNextSurface() {
     impeller::PipelineLibraryVK::Cast(*pipeline_library)
         .DidAcquireSurfaceFrame();
   }
-  parent_->GetCommandPoolRecycler()->Dispose();
+  DisposeThreadLocalCachedResources();
   parent_->GetResourceAllocator()->DebugTraceMemoryStatistics();
   return surface;
 }
diff --git a/impeller/renderer/backend/vulkan/tracked_objects_vk.cc b/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
index 47b8477309dcb..4bbaf94319d8c 100644
--- a/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
+++ b/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
@@ -11,8 +11,9 @@ namespace impeller {
 TrackedObjectsVK::TrackedObjectsVK(
     const std::weak_ptr<const ContextVK>& context,
     const std::shared_ptr<CommandPoolVK>& pool,
+    std::shared_ptr<DescriptorPoolVK> descriptor_pool,
     std::unique_ptr<GPUProbe> probe)
-    : desc_pool_(context), probe_(std::move(probe)) {
+    : desc_pool_(std::move(descriptor_pool)), probe_(std::move(probe)) {
   if (!pool) {
     return;
   }
@@ -78,7 +79,7 @@ vk::CommandBuffer TrackedObjectsVK::GetCommandBuffer() const {
 }
 
 DescriptorPoolVK& TrackedObjectsVK::GetDescriptorPool() {
-  return desc_pool_;
+  return *desc_pool_;
 }
 
 GPUProbe& TrackedObjectsVK::GetGPUProbe() const {
diff --git a/impeller/renderer/backend/vulkan/tracked_objects_vk.h b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
index b502eac1a2b20..8305f51160380 100644
--- a/impeller/renderer/backend/vulkan/tracked_objects_vk.h
+++ b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
@@ -20,6 +20,7 @@ class TrackedObjectsVK {
  public:
   explicit TrackedObjectsVK(const std::weak_ptr<const ContextVK>& context,
                             const std::shared_ptr<CommandPoolVK>& pool,
+                            std::shared_ptr<DescriptorPoolVK> descriptor_pool,
                             std::unique_ptr<GPUProbe> probe);
 
   ~TrackedObjectsVK();
@@ -43,7 +44,7 @@ class TrackedObjectsVK {
   GPUProbe& GetGPUProbe() const;
 
  private:
-  DescriptorPoolVK desc_pool_;
+  std::shared_ptr<DescriptorPoolVK> desc_pool_;
   // `shared_ptr` since command buffers have a link to the command pool.
   std::shared_ptr<CommandPoolVK> pool_;
   vk::UniqueCommandBuffer buffer_;

From 6ab44605f94dea34eed5b44fb1debdad46b70fac Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 17:02:17 -0700
Subject: [PATCH 02/11] add unit test.

---
 .../backend/vulkan/command_buffer_vk.cc       |  4 ++++
 .../backend/vulkan/command_buffer_vk.h        |  4 ++++
 .../vulkan/descriptor_pool_vk_unittests.cc    | 23 +++++++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/impeller/renderer/backend/vulkan/command_buffer_vk.cc b/impeller/renderer/backend/vulkan/command_buffer_vk.cc
index 3d432f3576ee3..e8341a352c8f9 100644
--- a/impeller/renderer/backend/vulkan/command_buffer_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_buffer_vk.cc
@@ -210,4 +210,8 @@ void CommandBufferVK::InsertDebugMarker(std::string_view label) const {
   }
 }
 
+DescriptorPoolVK& CommandBufferVK::GetDescriptorPool() const {
+  return tracked_objects_->GetDescriptorPool();
+}
+
 }  // namespace impeller
diff --git a/impeller/renderer/backend/vulkan/command_buffer_vk.h b/impeller/renderer/backend/vulkan/command_buffer_vk.h
index aee53db409a58..ef9dba2494975 100644
--- a/impeller/renderer/backend/vulkan/command_buffer_vk.h
+++ b/impeller/renderer/backend/vulkan/command_buffer_vk.h
@@ -8,6 +8,7 @@
 #include "fml/status_or.h"
 #include "impeller/base/backend_cast.h"
 #include "impeller/renderer/backend/vulkan/command_queue_vk.h"
+#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/texture_source_vk.h"
 #include "impeller/renderer/backend/vulkan/tracked_objects_vk.h"
@@ -81,6 +82,9 @@ class CommandBufferVK final
   // Visible for testing.
   bool IsTracking(const std::shared_ptr<const Texture>& texture) const;
 
+  // Visible for testing.
+  DescriptorPoolVK& GetDescriptorPool() const;
+
  private:
   friend class ContextVK;
   friend class CommandQueueVK;
diff --git a/impeller/renderer/backend/vulkan/descriptor_pool_vk_unittests.cc b/impeller/renderer/backend/vulkan/descriptor_pool_vk_unittests.cc
index 2deb9b3453642..fea47418dcdac 100644
--- a/impeller/renderer/backend/vulkan/descriptor_pool_vk_unittests.cc
+++ b/impeller/renderer/backend/vulkan/descriptor_pool_vk_unittests.cc
@@ -5,6 +5,7 @@
 #include "flutter/testing/testing.h"  // IWYU pragma: keep.
 #include "fml/closure.h"
 #include "fml/synchronization/waitable_event.h"
+#include "impeller/renderer/backend/vulkan/command_buffer_vk.h"
 #include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/resource_manager_vk.h"
 #include "impeller/renderer/backend/vulkan/test/mock_vulkan.h"
@@ -123,5 +124,27 @@ TEST(DescriptorPoolRecyclerVKTest, ReclaimDropsDescriptorPoolIfSizeIsExceeded) {
   context->Shutdown();
 }
 
+TEST(DescriptorPoolRecyclerVKTest, MultipleCommandBuffersShareDescriptorPool) {
+  auto const context = MockVulkanContextBuilder().Build();
+
+  auto cmd_buffer_1 = context->CreateCommandBuffer();
+  auto cmd_buffer_2 = context->CreateCommandBuffer();
+
+  CommandBufferVK& vk_1 = CommandBufferVK::Cast(*cmd_buffer_1);
+  CommandBufferVK& vk_2 = CommandBufferVK::Cast(*cmd_buffer_2);
+
+  EXPECT_EQ(&vk_1.GetDescriptorPool(), &vk_2.GetDescriptorPool());
+
+  // Resetting resources creates a new pool.
+  context->DisposeThreadLocalCachedResources();
+
+  auto cmd_buffer_3 = context->CreateCommandBuffer();
+  CommandBufferVK& vk_3 = CommandBufferVK::Cast(*cmd_buffer_3);
+
+  EXPECT_NE(&vk_1.GetDescriptorPool(), &vk_3.GetDescriptorPool());
+
+  context->Shutdown();
+}
+
 }  // namespace testing
 }  // namespace impeller

From 8432312dc17b189653d83677bbd97a0ae2bad9c7 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 17:03:32 -0700
Subject: [PATCH 03/11] fix comment.

---
 impeller/renderer/backend/vulkan/context_vk.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/context_vk.cc b/impeller/renderer/backend/vulkan/context_vk.cc
index 46e582a49b7b1..8bb17e9d10ad5 100644
--- a/impeller/renderer/backend/vulkan/context_vk.cc
+++ b/impeller/renderer/backend/vulkan/context_vk.cc
@@ -490,13 +490,13 @@ std::shared_ptr<PipelineLibrary> ContextVK::GetPipelineLibrary() const {
   return pipeline_library_;
 }
 
-// DescriptorPool Lifecycle:
+// DescriptorPool Lifecycle (Same as CommandPool lifecycle)
 // 1. End of frame will reset the descriptor pool (clearing this on a thread).
 //    There will still be references to the descriptor pool from the uncompleted
 //    command buffers.
 // 2. The last reference to the descriptor pool will be released from the fence
 //    waiter thread, which will schedule a task on the resource
-//    manager thread, which in turn will reset the command pool and make it
+//    manager thread, which in turn will reset the descriptor pool and make it
 //    available for reuse ("recycle").
 static thread_local std::shared_ptr<DescriptorPoolVK> tls_descriptor_pool;
 

From d973b2c1f8c9a1cf512b86e152fa261c051643b7 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 18:22:27 -0700
Subject: [PATCH 04/11] hook into existing TLS storage.

---
 .../backend/vulkan/command_pool_vk.cc         | 87 ++++++++++++++-----
 .../renderer/backend/vulkan/command_pool_vk.h | 20 +++++
 .../renderer/backend/vulkan/context_vk.cc     | 19 ++--
 impeller/renderer/backend/vulkan/context_vk.h |  2 -
 .../vulkan/test/mock_vulkan_unittests.cc      |  1 +
 .../backend/vulkan/tracked_objects_vk.cc      |  1 +
 .../backend/vulkan/tracked_objects_vk.h       |  2 +
 7 files changed, 93 insertions(+), 39 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.cc b/impeller/renderer/backend/vulkan/command_pool_vk.cc
index 9bb3d9d898621..c49dcfadd1e9c 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.cc
@@ -9,6 +9,7 @@
 #include <utility>
 
 #include "impeller/renderer/backend/vulkan/context_vk.h"
+#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/resource_manager_vk.h"
 
 #include "impeller/renderer/backend/vulkan/vk.h"  // IWYU pragma: keep.
@@ -155,10 +156,6 @@ void CommandPoolVK::Destroy() {
   collected_buffers_.clear();
 }
 
-// Associates a resource with a thread and context.
-using CommandPoolMap =
-    std::unordered_map<uint64_t, std::shared_ptr<CommandPoolVK>>;
-
 // CommandPoolVK Lifecycle:
 // 1. End of frame will reset the command pool (clearing this on a thread).
 //    There will still be references to the command pool from the uncompleted
@@ -169,17 +166,47 @@ using CommandPoolMap =
 //    available for reuse ("recycle").
 static thread_local std::unique_ptr<CommandPoolMap> tls_command_pool_map;
 
+struct WeakThreadLocalData {
+  std::weak_ptr<CommandPoolVK> command_pool;
+  std::weak_ptr<DescriptorPoolVK> descriptor_pool;
+};
+
 // Map each context to a list of all thread-local command pools associated
 // with that context.
 static Mutex g_all_pools_map_mutex;
-static std::unordered_map<
-    const ContextVK*,
-    std::vector<std::weak_ptr<CommandPoolVK>>> g_all_pools_map
+static std::unordered_map<const ContextVK*,
+                          std::vector<WeakThreadLocalData>> g_all_pools_map
     IPLR_GUARDED_BY(g_all_pools_map_mutex);
 
+std::shared_ptr<DescriptorPoolVK> CommandPoolRecyclerVK::GetDescriptorPool() {
+  const auto& strong_context = context_.lock();
+  if (!strong_context) {
+    return nullptr;
+  }
+
+  // If there is a resource in used for this thread and context, return it.
+  if (!tls_command_pool_map.get()) {
+    tls_command_pool_map.reset(new CommandPoolMap());
+  }
+  CommandPoolMap& pool_map = *tls_command_pool_map.get();
+  auto const hash = strong_context->GetHash();
+  auto const it = pool_map.find(hash);
+  if (it != pool_map.end()) {
+    return it->second.descriptor_pool;
+  }
+
+  const auto& result =
+      InitializeThreadLocalResources(strong_context, pool_map, hash);
+  if (result.has_value()) {
+    return result->descriptor_pool;
+  }
+
+  return nullptr;
+}
+
 // TODO(matanlurey): Return a status_or<> instead of nullptr when we have one.
 std::shared_ptr<CommandPoolVK> CommandPoolRecyclerVK::Get() {
-  auto const strong_context = context_.lock();
+  const auto& strong_context = context_.lock();
   if (!strong_context) {
     return nullptr;
   }
@@ -192,25 +219,40 @@ std::shared_ptr<CommandPoolVK> CommandPoolRecyclerVK::Get() {
   auto const hash = strong_context->GetHash();
   auto const it = pool_map.find(hash);
   if (it != pool_map.end()) {
-    return it->second;
+    return it->second.command_pool;
   }
 
-  // Otherwise, create a new resource and return it.
+  const auto& result =
+      InitializeThreadLocalResources(strong_context, pool_map, hash);
+  if (result.has_value()) {
+    return result->command_pool;
+  }
+
+  return nullptr;
+}
+
+std::optional<ThreadLocalData>
+CommandPoolRecyclerVK::InitializeThreadLocalResources(
+    const std::shared_ptr<ContextVK>& context,
+    CommandPoolMap& pool_map,
+    uint64_t pool_key) {
   auto data = Create();
   if (!data || !data->pool) {
-    return nullptr;
+    return std::nullopt;
   }
 
-  auto const resource = std::make_shared<CommandPoolVK>(
+  auto command_pool = std::make_shared<CommandPoolVK>(
       std::move(data->pool), std::move(data->buffers), context_);
-  pool_map.emplace(hash, resource);
-
+  auto descriptor_pool = std::make_shared<DescriptorPoolVK>(context_);
   {
     Lock all_pools_lock(g_all_pools_map_mutex);
-    g_all_pools_map[strong_context.get()].push_back(resource);
+    g_all_pools_map[context.get()].push_back(WeakThreadLocalData{
+        .command_pool = command_pool, .descriptor_pool = descriptor_pool});
   }
 
-  return resource;
+  return pool_map[pool_key] =
+             ThreadLocalData{.command_pool = std::move(command_pool),
+                             .descriptor_pool = std::move(descriptor_pool)};
 }
 
 // TODO(matanlurey): Return a status_or<> instead of nullopt when we have one.
@@ -293,14 +335,13 @@ void CommandPoolRecyclerVK::DestroyThreadLocalPools(const ContextVK* context) {
   Lock all_pools_lock(g_all_pools_map_mutex);
   auto found = g_all_pools_map.find(context);
   if (found != g_all_pools_map.end()) {
-    for (auto& weak_pool : found->second) {
-      auto pool = weak_pool.lock();
-      if (!pool) {
-        continue;
+    for (auto& [command_pool, desc_pool] : found->second) {
+      const auto& strong_pool = command_pool.lock();
+      if (strong_pool) {
+        // Delete all objects held by this pool.  The destroyed pool will still
+        // remain in its thread's TLS map until that thread exits.
+        strong_pool->Destroy();
       }
-      // Delete all objects held by this pool.  The destroyed pool will still
-      // remain in its thread's TLS map until that thread exits.
-      pool->Destroy();
     }
     g_all_pools_map.erase(found);
   }
diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.h b/impeller/renderer/backend/vulkan/command_pool_vk.h
index dd60026b44f70..662d03422416f 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.h
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.h
@@ -10,6 +10,7 @@
 #include <utility>
 
 #include "impeller/base/thread.h"
+#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/vk.h"  // IWYU pragma: keep.
 #include "vulkan/vulkan_handles.hpp"
 
@@ -76,6 +77,15 @@ class CommandPoolVK final {
       pool_mutex_);
 };
 
+struct ThreadLocalData {
+  std::shared_ptr<CommandPoolVK> command_pool;
+  std::shared_ptr<DescriptorPoolVK> descriptor_pool;
+};
+
+// Associates a resource with a thread and context.
+using CommandPoolMap =
+    std::unordered_map<uint64_t, ThreadLocalData>;
+
 //------------------------------------------------------------------------------
 /// @brief      Creates and manages the lifecycle of |vk::CommandPool| objects.
 ///
@@ -128,6 +138,11 @@ class CommandPoolRecyclerVK final
   /// @warning    Returns a |nullptr| if a pool could not be created.
   std::shared_ptr<CommandPoolVK> Get();
 
+  /// @brief      Gets a descriptor pool for the current thread.
+  ///
+  /// @warning    Returns a |nullptr| if a pool could not be created.
+  std::shared_ptr<DescriptorPoolVK> GetDescriptorPool();
+
   /// @brief      Returns a command pool to be reset on a background thread.
   ///
   /// @param[in]  pool The pool to recycler.
@@ -153,6 +168,11 @@ class CommandPoolRecyclerVK final
   /// @returns    Returns a |std::nullopt| if a pool was not available.
   std::optional<RecycledData> Reuse();
 
+  /// Create a DescriptorPoolVK and a CommandPoolVK and stash them in the TLS
+  /// map.
+  std::optional<ThreadLocalData> InitializeThreadLocalResources(
+      const std::shared_ptr<ContextVK>& context, CommandPoolMap& pool_map, uint64_t pool_key);
+
   CommandPoolRecyclerVK(const CommandPoolRecyclerVK&) = delete;
 
   CommandPoolRecyclerVK& operator=(const CommandPoolRecyclerVK&) = delete;
diff --git a/impeller/renderer/backend/vulkan/context_vk.cc b/impeller/renderer/backend/vulkan/context_vk.cc
index 8bb17e9d10ad5..9ce57fa19af36 100644
--- a/impeller/renderer/backend/vulkan/context_vk.cc
+++ b/impeller/renderer/backend/vulkan/context_vk.cc
@@ -490,27 +490,19 @@ std::shared_ptr<PipelineLibrary> ContextVK::GetPipelineLibrary() const {
   return pipeline_library_;
 }
 
-// DescriptorPool Lifecycle (Same as CommandPool lifecycle)
-// 1. End of frame will reset the descriptor pool (clearing this on a thread).
-//    There will still be references to the descriptor pool from the uncompleted
-//    command buffers.
-// 2. The last reference to the descriptor pool will be released from the fence
-//    waiter thread, which will schedule a task on the resource
-//    manager thread, which in turn will reset the descriptor pool and make it
-//    available for reuse ("recycle").
-static thread_local std::shared_ptr<DescriptorPoolVK> tls_descriptor_pool;
-
 std::shared_ptr<CommandBuffer> ContextVK::CreateCommandBuffer() const {
   const auto& recycler = GetCommandPoolRecycler();
   auto tls_pool = recycler->Get();
   if (!tls_pool) {
     return nullptr;
   }
-  if (!tls_descriptor_pool) {
-    tls_descriptor_pool = std::make_shared<DescriptorPoolVK>(weak_from_this());
+  auto tls_desc_pool = recycler->GetDescriptorPool();
+  if (!tls_desc_pool) {
+    return nullptr;
   }
+
   auto tracked_objects = std::make_shared<TrackedObjectsVK>(
-      weak_from_this(), std::move(tls_pool), tls_descriptor_pool,
+      weak_from_this(), std::move(tls_pool), tls_desc_pool,
       GetGPUTracer()->CreateGPUProbe());
   auto queue = GetGraphicsQueue();
 
@@ -644,7 +636,6 @@ void ContextVK::InitializeCommonlyUsedShadersIfNeeded() const {
 
 void ContextVK::DisposeThreadLocalCachedResources() {
   command_pool_recycler_->Dispose();
-  tls_descriptor_pool.reset();
 }
 
 const std::shared_ptr<YUVConversionLibraryVK>&
diff --git a/impeller/renderer/backend/vulkan/context_vk.h b/impeller/renderer/backend/vulkan/context_vk.h
index fe7f4da002f91..5e7f134fab10a 100644
--- a/impeller/renderer/backend/vulkan/context_vk.h
+++ b/impeller/renderer/backend/vulkan/context_vk.h
@@ -10,10 +10,8 @@
 #include "flutter/fml/concurrent_message_loop.h"
 #include "flutter/fml/mapping.h"
 #include "flutter/fml/unique_fd.h"
-#include "fml/thread.h"
 #include "impeller/base/backend_cast.h"
 #include "impeller/core/formats.h"
-#include "impeller/renderer/backend/vulkan/command_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/driver_info_vk.h"
 #include "impeller/renderer/backend/vulkan/pipeline_library_vk.h"
diff --git a/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc b/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
index 2555994a8fd03..092e7c7da7e8f 100644
--- a/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
+++ b/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
@@ -5,6 +5,7 @@
 #include "flutter/testing/testing.h"  // IWYU pragma: keep
 #include "gtest/gtest.h"
 #include "impeller/renderer/backend/vulkan/test/mock_vulkan.h"
+#include "impeller/renderer/backend/vulkan/command_pool_vk.h"
 #include "vulkan/vulkan_enums.hpp"
 
 namespace impeller {
diff --git a/impeller/renderer/backend/vulkan/tracked_objects_vk.cc b/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
index 4bbaf94319d8c..249d2483b01b9 100644
--- a/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
+++ b/impeller/renderer/backend/vulkan/tracked_objects_vk.cc
@@ -4,6 +4,7 @@
 
 #include "impeller/renderer/backend/vulkan/tracked_objects_vk.h"
 
+#include "impeller/renderer/backend/vulkan/command_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/gpu_tracer_vk.h"
 
 namespace impeller {
diff --git a/impeller/renderer/backend/vulkan/tracked_objects_vk.h b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
index 8305f51160380..4ac72bc886e43 100644
--- a/impeller/renderer/backend/vulkan/tracked_objects_vk.h
+++ b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
@@ -14,6 +14,8 @@
 
 namespace impeller {
 
+class CommandPoolVK;
+
 /// @brief A per-frame object used to track resource lifetimes and allocate
 ///        command buffers and descriptor sets.
 class TrackedObjectsVK {

From 0ae06a820834aa1722b4ee3b12e28368cd2c7e16 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 18:22:49 -0700
Subject: [PATCH 05/11] ++

---
 impeller/renderer/backend/vulkan/surface_context_vk.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/impeller/renderer/backend/vulkan/surface_context_vk.cc b/impeller/renderer/backend/vulkan/surface_context_vk.cc
index b5ddd61a04e01..912c74b03c056 100644
--- a/impeller/renderer/backend/vulkan/surface_context_vk.cc
+++ b/impeller/renderer/backend/vulkan/surface_context_vk.cc
@@ -86,7 +86,7 @@ std::unique_ptr<Surface> SurfaceContextVK::AcquireNextSurface() {
     impeller::PipelineLibraryVK::Cast(*pipeline_library)
         .DidAcquireSurfaceFrame();
   }
-  DisposeThreadLocalCachedResources();
+  parent_->GetCommandPoolRecycler()->Dispose();
   parent_->GetResourceAllocator()->DebugTraceMemoryStatistics();
   return surface;
 }

From a7398b93d0a263a56a23da5761eb037f570d2134 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 17 Oct 2024 18:24:55 -0700
Subject: [PATCH 06/11] ++

---
 impeller/renderer/backend/vulkan/command_pool_vk.h         | 7 ++++---
 .../renderer/backend/vulkan/test/mock_vulkan_unittests.cc  | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.h b/impeller/renderer/backend/vulkan/command_pool_vk.h
index 662d03422416f..55fec9b35137c 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.h
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.h
@@ -83,8 +83,7 @@ struct ThreadLocalData {
 };
 
 // Associates a resource with a thread and context.
-using CommandPoolMap =
-    std::unordered_map<uint64_t, ThreadLocalData>;
+using CommandPoolMap = std::unordered_map<uint64_t, ThreadLocalData>;
 
 //------------------------------------------------------------------------------
 /// @brief      Creates and manages the lifecycle of |vk::CommandPool| objects.
@@ -171,7 +170,9 @@ class CommandPoolRecyclerVK final
   /// Create a DescriptorPoolVK and a CommandPoolVK and stash them in the TLS
   /// map.
   std::optional<ThreadLocalData> InitializeThreadLocalResources(
-      const std::shared_ptr<ContextVK>& context, CommandPoolMap& pool_map, uint64_t pool_key);
+      const std::shared_ptr<ContextVK>& context,
+      CommandPoolMap& pool_map,
+      uint64_t pool_key);
 
   CommandPoolRecyclerVK(const CommandPoolRecyclerVK&) = delete;
 
diff --git a/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc b/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
index 092e7c7da7e8f..1688b12e49c46 100644
--- a/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
+++ b/impeller/renderer/backend/vulkan/test/mock_vulkan_unittests.cc
@@ -4,8 +4,8 @@
 
 #include "flutter/testing/testing.h"  // IWYU pragma: keep
 #include "gtest/gtest.h"
-#include "impeller/renderer/backend/vulkan/test/mock_vulkan.h"
 #include "impeller/renderer/backend/vulkan/command_pool_vk.h"
+#include "impeller/renderer/backend/vulkan/test/mock_vulkan.h"
 #include "vulkan/vulkan_enums.hpp"
 
 namespace impeller {

From 29c9dce790539bb619507a1aa48056a67fbabb15 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Fri, 18 Oct 2024 13:33:09 -0700
Subject: [PATCH 07/11] ++

---
 impeller/renderer/backend/vulkan/command_pool_vk.cc    | 6 +++++-
 impeller/renderer/backend/vulkan/descriptor_pool_vk.cc | 4 ++++
 impeller/renderer/backend/vulkan/descriptor_pool_vk.h  | 2 ++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.cc b/impeller/renderer/backend/vulkan/command_pool_vk.cc
index c49dcfadd1e9c..e0357577ce9c8 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.cc
@@ -336,12 +336,16 @@ void CommandPoolRecyclerVK::DestroyThreadLocalPools(const ContextVK* context) {
   auto found = g_all_pools_map.find(context);
   if (found != g_all_pools_map.end()) {
     for (auto& [command_pool, desc_pool] : found->second) {
-      const auto& strong_pool = command_pool.lock();
+      const auto strong_pool = command_pool.lock();
       if (strong_pool) {
         // Delete all objects held by this pool.  The destroyed pool will still
         // remain in its thread's TLS map until that thread exits.
         strong_pool->Destroy();
       }
+      const auto strong_desc_pool = desc_pool.lock();
+      if (strong_desc_pool) {
+        strong_pool->Destroy();
+      }
     }
     g_all_pools_map.erase(found);
   }
diff --git a/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc b/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
index c7545ea9a156d..a6b24b64cbbb4 100644
--- a/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
@@ -91,6 +91,10 @@ DescriptorPoolVK::~DescriptorPoolVK() {
   pools_.clear();
 }
 
+void DescriptorPoolVK::Destroy() {
+  pools_.clear();
+}
+
 fml::StatusOr<vk::DescriptorSet> DescriptorPoolVK::AllocateDescriptorSets(
     const vk::DescriptorSetLayout& layout,
     const ContextVK& context_vk) {
diff --git a/impeller/renderer/backend/vulkan/descriptor_pool_vk.h b/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
index 53f35a94ab890..ef4ac23553e14 100644
--- a/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
+++ b/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
@@ -34,6 +34,8 @@ class DescriptorPoolVK {
       const vk::DescriptorSetLayout& layout,
       const ContextVK& context_vk);
 
+  void Destroy();
+
  private:
   std::weak_ptr<const ContextVK> context_;
   std::vector<vk::UniqueDescriptorPool> pools_;

From f5efff60a826454b02ac74b69776e43aad819798 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Fri, 18 Oct 2024 14:09:43 -0700
Subject: [PATCH 08/11] ++

---
 .../backend/vulkan/command_pool_vk.cc         | 19 +++++--------------
 impeller/renderer/backend/vulkan/context_vk.h |  2 +-
 .../backend/vulkan/descriptor_pool_vk.cc      |  4 ----
 3 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.cc b/impeller/renderer/backend/vulkan/command_pool_vk.cc
index e0357577ce9c8..7d46e00aa93b9 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.cc
@@ -166,16 +166,12 @@ void CommandPoolVK::Destroy() {
 //    available for reuse ("recycle").
 static thread_local std::unique_ptr<CommandPoolMap> tls_command_pool_map;
 
-struct WeakThreadLocalData {
-  std::weak_ptr<CommandPoolVK> command_pool;
-  std::weak_ptr<DescriptorPoolVK> descriptor_pool;
-};
-
 // Map each context to a list of all thread-local command pools associated
 // with that context.
 static Mutex g_all_pools_map_mutex;
-static std::unordered_map<const ContextVK*,
-                          std::vector<WeakThreadLocalData>> g_all_pools_map
+static std::unordered_map<
+    const ContextVK*,
+    std::vector<std::weak_ptr<CommandPoolVK>>> g_all_pools_map
     IPLR_GUARDED_BY(g_all_pools_map_mutex);
 
 std::shared_ptr<DescriptorPoolVK> CommandPoolRecyclerVK::GetDescriptorPool() {
@@ -246,8 +242,7 @@ CommandPoolRecyclerVK::InitializeThreadLocalResources(
   auto descriptor_pool = std::make_shared<DescriptorPoolVK>(context_);
   {
     Lock all_pools_lock(g_all_pools_map_mutex);
-    g_all_pools_map[context.get()].push_back(WeakThreadLocalData{
-        .command_pool = command_pool, .descriptor_pool = descriptor_pool});
+    g_all_pools_map[context.get()].push_back(command_pool);
   }
 
   return pool_map[pool_key] =
@@ -335,17 +330,13 @@ void CommandPoolRecyclerVK::DestroyThreadLocalPools(const ContextVK* context) {
   Lock all_pools_lock(g_all_pools_map_mutex);
   auto found = g_all_pools_map.find(context);
   if (found != g_all_pools_map.end()) {
-    for (auto& [command_pool, desc_pool] : found->second) {
+    for (auto& command_pool : found->second) {
       const auto strong_pool = command_pool.lock();
       if (strong_pool) {
         // Delete all objects held by this pool.  The destroyed pool will still
         // remain in its thread's TLS map until that thread exits.
         strong_pool->Destroy();
       }
-      const auto strong_desc_pool = desc_pool.lock();
-      if (strong_desc_pool) {
-        strong_pool->Destroy();
-      }
     }
     g_all_pools_map.erase(found);
   }
diff --git a/impeller/renderer/backend/vulkan/context_vk.h b/impeller/renderer/backend/vulkan/context_vk.h
index 5e7f134fab10a..abd8811b7ba65 100644
--- a/impeller/renderer/backend/vulkan/context_vk.h
+++ b/impeller/renderer/backend/vulkan/context_vk.h
@@ -201,11 +201,11 @@ class ContextVK final : public Context,
   std::shared_ptr<const Capabilities> device_capabilities_;
   std::shared_ptr<FenceWaiterVK> fence_waiter_;
   std::shared_ptr<ResourceManagerVK> resource_manager_;
+  std::shared_ptr<DescriptorPoolRecyclerVK> descriptor_pool_recycler_;
   std::shared_ptr<CommandPoolRecyclerVK> command_pool_recycler_;
   std::string device_name_;
   std::shared_ptr<fml::ConcurrentMessageLoop> raster_message_loop_;
   std::shared_ptr<GPUTracerVK> gpu_tracer_;
-  std::shared_ptr<DescriptorPoolRecyclerVK> descriptor_pool_recycler_;
   std::shared_ptr<CommandQueue> command_queue_vk_;
   bool should_disable_surface_control_ = false;
 
diff --git a/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc b/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
index a6b24b64cbbb4..c7545ea9a156d 100644
--- a/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
@@ -91,10 +91,6 @@ DescriptorPoolVK::~DescriptorPoolVK() {
   pools_.clear();
 }
 
-void DescriptorPoolVK::Destroy() {
-  pools_.clear();
-}
-
 fml::StatusOr<vk::DescriptorSet> DescriptorPoolVK::AllocateDescriptorSets(
     const vk::DescriptorSetLayout& layout,
     const ContextVK& context_vk) {

From 441daf5f47ccc5dbafdd8d5f85c3b0523d32a48a Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Fri, 18 Oct 2024 23:01:27 -0700
Subject: [PATCH 09/11] ++

---
 .ci.yaml | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/.ci.yaml b/.ci.yaml
index 205edfe43306c..64234fe4970d2 100644
--- a/.ci.yaml
+++ b/.ci.yaml
@@ -85,14 +85,14 @@ targets:
           {"dependency": "goldctl", "version": "git_revision:720a542f6fe4f92922c3b8f0fdcc4d2ac6bb83cd"}
         ]
     timeout: 90
-    runIf:
-      - .ci.yaml
-      - ci/builders/linux_android_emulator.json
-      - DEPS
-      - lib/ui/**
-      - shell/platform/android/**
-      - testing/scenario_app/**
-      - testing/skia_gold_client/**
+    # runIf:
+    #   - .ci.yaml
+    #   - ci/builders/linux_android_emulator.json
+    #   - DEPS
+    #   - lib/ui/**
+    #   - shell/platform/android/**
+    #   - testing/scenario_app/**
+    #   - testing/skia_gold_client/**
 
   - name: Linux linux_android_emulator_opengles_tests_34
     enabled_branches:

From 1262955eae72cb73d623bdeeac597e8daed5d1d2 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sun, 20 Oct 2024 10:48:00 -0700
Subject: [PATCH 10/11] move to its own map

---
 .../backend/vulkan/command_pool_vk.cc         | 76 +++++--------------
 .../renderer/backend/vulkan/command_pool_vk.h | 21 -----
 .../renderer/backend/vulkan/context_vk.cc     | 21 ++++-
 impeller/renderer/backend/vulkan/context_vk.h |  7 ++
 .../backend/vulkan/descriptor_pool_vk.h       |  2 -
 .../backend/vulkan/surface_context_vk.cc      |  2 +-
 .../backend/vulkan/tracked_objects_vk.h       |  2 -
 7 files changed, 45 insertions(+), 86 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.cc b/impeller/renderer/backend/vulkan/command_pool_vk.cc
index 7d46e00aa93b9..9bb3d9d898621 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.cc
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.cc
@@ -9,7 +9,6 @@
 #include <utility>
 
 #include "impeller/renderer/backend/vulkan/context_vk.h"
-#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/resource_manager_vk.h"
 
 #include "impeller/renderer/backend/vulkan/vk.h"  // IWYU pragma: keep.
@@ -156,6 +155,10 @@ void CommandPoolVK::Destroy() {
   collected_buffers_.clear();
 }
 
+// Associates a resource with a thread and context.
+using CommandPoolMap =
+    std::unordered_map<uint64_t, std::shared_ptr<CommandPoolVK>>;
+
 // CommandPoolVK Lifecycle:
 // 1. End of frame will reset the command pool (clearing this on a thread).
 //    There will still be references to the command pool from the uncompleted
@@ -174,35 +177,9 @@ static std::unordered_map<
     std::vector<std::weak_ptr<CommandPoolVK>>> g_all_pools_map
     IPLR_GUARDED_BY(g_all_pools_map_mutex);
 
-std::shared_ptr<DescriptorPoolVK> CommandPoolRecyclerVK::GetDescriptorPool() {
-  const auto& strong_context = context_.lock();
-  if (!strong_context) {
-    return nullptr;
-  }
-
-  // If there is a resource in used for this thread and context, return it.
-  if (!tls_command_pool_map.get()) {
-    tls_command_pool_map.reset(new CommandPoolMap());
-  }
-  CommandPoolMap& pool_map = *tls_command_pool_map.get();
-  auto const hash = strong_context->GetHash();
-  auto const it = pool_map.find(hash);
-  if (it != pool_map.end()) {
-    return it->second.descriptor_pool;
-  }
-
-  const auto& result =
-      InitializeThreadLocalResources(strong_context, pool_map, hash);
-  if (result.has_value()) {
-    return result->descriptor_pool;
-  }
-
-  return nullptr;
-}
-
 // TODO(matanlurey): Return a status_or<> instead of nullptr when we have one.
 std::shared_ptr<CommandPoolVK> CommandPoolRecyclerVK::Get() {
-  const auto& strong_context = context_.lock();
+  auto const strong_context = context_.lock();
   if (!strong_context) {
     return nullptr;
   }
@@ -215,39 +192,25 @@ std::shared_ptr<CommandPoolVK> CommandPoolRecyclerVK::Get() {
   auto const hash = strong_context->GetHash();
   auto const it = pool_map.find(hash);
   if (it != pool_map.end()) {
-    return it->second.command_pool;
+    return it->second;
   }
 
-  const auto& result =
-      InitializeThreadLocalResources(strong_context, pool_map, hash);
-  if (result.has_value()) {
-    return result->command_pool;
-  }
-
-  return nullptr;
-}
-
-std::optional<ThreadLocalData>
-CommandPoolRecyclerVK::InitializeThreadLocalResources(
-    const std::shared_ptr<ContextVK>& context,
-    CommandPoolMap& pool_map,
-    uint64_t pool_key) {
+  // Otherwise, create a new resource and return it.
   auto data = Create();
   if (!data || !data->pool) {
-    return std::nullopt;
+    return nullptr;
   }
 
-  auto command_pool = std::make_shared<CommandPoolVK>(
+  auto const resource = std::make_shared<CommandPoolVK>(
       std::move(data->pool), std::move(data->buffers), context_);
-  auto descriptor_pool = std::make_shared<DescriptorPoolVK>(context_);
+  pool_map.emplace(hash, resource);
+
   {
     Lock all_pools_lock(g_all_pools_map_mutex);
-    g_all_pools_map[context.get()].push_back(command_pool);
+    g_all_pools_map[strong_context.get()].push_back(resource);
   }
 
-  return pool_map[pool_key] =
-             ThreadLocalData{.command_pool = std::move(command_pool),
-                             .descriptor_pool = std::move(descriptor_pool)};
+  return resource;
 }
 
 // TODO(matanlurey): Return a status_or<> instead of nullopt when we have one.
@@ -330,13 +293,14 @@ void CommandPoolRecyclerVK::DestroyThreadLocalPools(const ContextVK* context) {
   Lock all_pools_lock(g_all_pools_map_mutex);
   auto found = g_all_pools_map.find(context);
   if (found != g_all_pools_map.end()) {
-    for (auto& command_pool : found->second) {
-      const auto strong_pool = command_pool.lock();
-      if (strong_pool) {
-        // Delete all objects held by this pool.  The destroyed pool will still
-        // remain in its thread's TLS map until that thread exits.
-        strong_pool->Destroy();
+    for (auto& weak_pool : found->second) {
+      auto pool = weak_pool.lock();
+      if (!pool) {
+        continue;
       }
+      // Delete all objects held by this pool.  The destroyed pool will still
+      // remain in its thread's TLS map until that thread exits.
+      pool->Destroy();
     }
     g_all_pools_map.erase(found);
   }
diff --git a/impeller/renderer/backend/vulkan/command_pool_vk.h b/impeller/renderer/backend/vulkan/command_pool_vk.h
index 55fec9b35137c..dd60026b44f70 100644
--- a/impeller/renderer/backend/vulkan/command_pool_vk.h
+++ b/impeller/renderer/backend/vulkan/command_pool_vk.h
@@ -10,7 +10,6 @@
 #include <utility>
 
 #include "impeller/base/thread.h"
-#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/vk.h"  // IWYU pragma: keep.
 #include "vulkan/vulkan_handles.hpp"
 
@@ -77,14 +76,6 @@ class CommandPoolVK final {
       pool_mutex_);
 };
 
-struct ThreadLocalData {
-  std::shared_ptr<CommandPoolVK> command_pool;
-  std::shared_ptr<DescriptorPoolVK> descriptor_pool;
-};
-
-// Associates a resource with a thread and context.
-using CommandPoolMap = std::unordered_map<uint64_t, ThreadLocalData>;
-
 //------------------------------------------------------------------------------
 /// @brief      Creates and manages the lifecycle of |vk::CommandPool| objects.
 ///
@@ -137,11 +128,6 @@ class CommandPoolRecyclerVK final
   /// @warning    Returns a |nullptr| if a pool could not be created.
   std::shared_ptr<CommandPoolVK> Get();
 
-  /// @brief      Gets a descriptor pool for the current thread.
-  ///
-  /// @warning    Returns a |nullptr| if a pool could not be created.
-  std::shared_ptr<DescriptorPoolVK> GetDescriptorPool();
-
   /// @brief      Returns a command pool to be reset on a background thread.
   ///
   /// @param[in]  pool The pool to recycler.
@@ -167,13 +153,6 @@ class CommandPoolRecyclerVK final
   /// @returns    Returns a |std::nullopt| if a pool was not available.
   std::optional<RecycledData> Reuse();
 
-  /// Create a DescriptorPoolVK and a CommandPoolVK and stash them in the TLS
-  /// map.
-  std::optional<ThreadLocalData> InitializeThreadLocalResources(
-      const std::shared_ptr<ContextVK>& context,
-      CommandPoolMap& pool_map,
-      uint64_t pool_key);
-
   CommandPoolRecyclerVK(const CommandPoolRecyclerVK&) = delete;
 
   CommandPoolRecyclerVK& operator=(const CommandPoolRecyclerVK&) = delete;
diff --git a/impeller/renderer/backend/vulkan/context_vk.cc b/impeller/renderer/backend/vulkan/context_vk.cc
index 9ce57fa19af36..d2092bb961d29 100644
--- a/impeller/renderer/backend/vulkan/context_vk.cc
+++ b/impeller/renderer/backend/vulkan/context_vk.cc
@@ -3,6 +3,8 @@
 // found in the LICENSE file.
 
 #include "impeller/renderer/backend/vulkan/context_vk.h"
+#include <thread>
+#include <unordered_map>
 
 #include "fml/concurrent_message_loop.h"
 #include "impeller/renderer/backend/vulkan/command_queue_vk.h"
@@ -31,6 +33,7 @@
 #include "impeller/renderer/backend/vulkan/command_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/command_queue_vk.h"
 #include "impeller/renderer/backend/vulkan/debug_report_vk.h"
+#include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/fence_waiter_vk.h"
 #include "impeller/renderer/backend/vulkan/gpu_tracer_vk.h"
 #include "impeller/renderer/backend/vulkan/resource_manager_vk.h"
@@ -496,13 +499,22 @@ std::shared_ptr<CommandBuffer> ContextVK::CreateCommandBuffer() const {
   if (!tls_pool) {
     return nullptr;
   }
-  auto tls_desc_pool = recycler->GetDescriptorPool();
-  if (!tls_desc_pool) {
-    return nullptr;
+
+  // look up a cached descriptor pool for the current frame and reuse it
+  // if it exists, otherwise create a new pool.
+  DescriptorPoolMap::iterator current_pool =
+      cached_descriptor_pool_.find(std::this_thread::get_id());
+  std::shared_ptr<DescriptorPoolVK> descriptor_pool;
+  if (current_pool == cached_descriptor_pool_.end()) {
+    descriptor_pool =
+        (cached_descriptor_pool_[std::this_thread::get_id()] =
+             std::make_shared<DescriptorPoolVK>(weak_from_this()));
+  } else {
+    descriptor_pool = current_pool->second;
   }
 
   auto tracked_objects = std::make_shared<TrackedObjectsVK>(
-      weak_from_this(), std::move(tls_pool), tls_desc_pool,
+      weak_from_this(), std::move(tls_pool), std::move(descriptor_pool),
       GetGPUTracer()->CreateGPUProbe());
   auto queue = GetGraphicsQueue();
 
@@ -635,6 +647,7 @@ void ContextVK::InitializeCommonlyUsedShadersIfNeeded() const {
 }
 
 void ContextVK::DisposeThreadLocalCachedResources() {
+  cached_descriptor_pool_.erase(std::this_thread::get_id());
   command_pool_recycler_->Dispose();
 }
 
diff --git a/impeller/renderer/backend/vulkan/context_vk.h b/impeller/renderer/backend/vulkan/context_vk.h
index abd8811b7ba65..c6ccc280bc147 100644
--- a/impeller/renderer/backend/vulkan/context_vk.h
+++ b/impeller/renderer/backend/vulkan/context_vk.h
@@ -12,6 +12,7 @@
 #include "flutter/fml/unique_fd.h"
 #include "impeller/base/backend_cast.h"
 #include "impeller/core/formats.h"
+#include "impeller/renderer/backend/vulkan/command_pool_vk.h"
 #include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/driver_info_vk.h"
 #include "impeller/renderer/backend/vulkan/pipeline_library_vk.h"
@@ -36,6 +37,7 @@ class SurfaceContextVK;
 class GPUTracerVK;
 class DescriptorPoolRecyclerVK;
 class CommandQueueVK;
+class DescriptorPoolVK;
 
 class ContextVK final : public Context,
                         public BackendCast<ContextVK, Context>,
@@ -207,6 +209,11 @@ class ContextVK final : public Context,
   std::shared_ptr<fml::ConcurrentMessageLoop> raster_message_loop_;
   std::shared_ptr<GPUTracerVK> gpu_tracer_;
   std::shared_ptr<CommandQueue> command_queue_vk_;
+
+  using DescriptorPoolMap =
+      std::unordered_map<std::thread::id, std::shared_ptr<DescriptorPoolVK>>;
+
+  mutable DescriptorPoolMap cached_descriptor_pool_;
   bool should_disable_surface_control_ = false;
 
   const uint64_t hash_;
diff --git a/impeller/renderer/backend/vulkan/descriptor_pool_vk.h b/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
index ef4ac23553e14..53f35a94ab890 100644
--- a/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
+++ b/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
@@ -34,8 +34,6 @@ class DescriptorPoolVK {
       const vk::DescriptorSetLayout& layout,
       const ContextVK& context_vk);
 
-  void Destroy();
-
  private:
   std::weak_ptr<const ContextVK> context_;
   std::vector<vk::UniqueDescriptorPool> pools_;
diff --git a/impeller/renderer/backend/vulkan/surface_context_vk.cc b/impeller/renderer/backend/vulkan/surface_context_vk.cc
index 912c74b03c056..dd1708c8f266d 100644
--- a/impeller/renderer/backend/vulkan/surface_context_vk.cc
+++ b/impeller/renderer/backend/vulkan/surface_context_vk.cc
@@ -86,7 +86,7 @@ std::unique_ptr<Surface> SurfaceContextVK::AcquireNextSurface() {
     impeller::PipelineLibraryVK::Cast(*pipeline_library)
         .DidAcquireSurfaceFrame();
   }
-  parent_->GetCommandPoolRecycler()->Dispose();
+  parent_->DisposeThreadLocalCachedResources();
   parent_->GetResourceAllocator()->DebugTraceMemoryStatistics();
   return surface;
 }
diff --git a/impeller/renderer/backend/vulkan/tracked_objects_vk.h b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
index 4ac72bc886e43..8305f51160380 100644
--- a/impeller/renderer/backend/vulkan/tracked_objects_vk.h
+++ b/impeller/renderer/backend/vulkan/tracked_objects_vk.h
@@ -14,8 +14,6 @@
 
 namespace impeller {
 
-class CommandPoolVK;
-
 /// @brief A per-frame object used to track resource lifetimes and allocate
 ///        command buffers and descriptor sets.
 class TrackedObjectsVK {

From 988694f98ca59874b6b189d3227e32278ad971c5 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Mon, 21 Oct 2024 11:20:10 -0700
Subject: [PATCH 11/11] Revert ci yaml

---
 .ci.yaml | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/.ci.yaml b/.ci.yaml
index 64234fe4970d2..239cce546881e 100644
--- a/.ci.yaml
+++ b/.ci.yaml
@@ -85,14 +85,14 @@ targets:
           {"dependency": "goldctl", "version": "git_revision:720a542f6fe4f92922c3b8f0fdcc4d2ac6bb83cd"}
         ]
     timeout: 90
-    # runIf:
-    #   - .ci.yaml
-    #   - ci/builders/linux_android_emulator.json
-    #   - DEPS
-    #   - lib/ui/**
-    #   - shell/platform/android/**
-    #   - testing/scenario_app/**
-    #   - testing/skia_gold_client/**
+    runIf:
+      - .ci.yaml
+      - ci/builders/linux_android_emulator.json
+      - DEPS
+      - lib/ui/**
+      - shell/platform/android/**
+      - testing/scenario_app/**
+      - testing/skia_gold_client/**
 
   - name: Linux linux_android_emulator_opengles_tests_34
     enabled_branches:
@@ -506,6 +506,7 @@ targets:
   # Avoid using a Mac orchestrator to save ~5 minutes of Mac host time.
   - name: Linux mac_clangd
     recipe: engine_v2/engine_v2
+    timeout: 90
     # Do not remove(https://github.com/flutter/flutter/issues/144644)
     # Scheduler will fail to get the platform
     drone_dimensions: