diff --git a/Source/Async/AuGroupState.cpp b/Source/Async/AuGroupState.cpp
index f65025ac..ad6bfa01 100644
--- a/Source/Async/AuGroupState.cpp
+++ b/Source/Async/AuGroupState.cpp
@@ -20,12 +20,14 @@ namespace Aurora::Async
 
     AuSPtr<ThreadState> GroupState::GetThreadByIndex(ThreadId_t uIndex)
     {
-        // TODO: deinit mutex
-        if (AuArraySize(this->wpWorkers) > uIndex)
         {
-            if (auto pState = AuTryLockMemoryType(this->wpWorkers[uIndex]))
+            AU_LOCK_GUARD(this->deinitMutex);
+            if (AuArraySize(this->wpWorkers) > uIndex)
             {
-                return pState;
+                if (auto pState = AuTryLockMemoryType(this->wpWorkers[uIndex]))
+                {
+                    return pState;
+                }
             }
         }
 
@@ -41,9 +43,12 @@ namespace Aurora::Async
 
     void GroupState::Decommit(ThreadId_t id)
     {
-        if (AuArraySize(this->wpWorkers) > id)
         {
-            this->wpWorkers[id] = {};
+            AU_LOCK_GUARD(this->deinitMutex);
+            if (AuArraySize(this->wpWorkers) > id)
+            {
+                this->wpWorkers[id] = {};
+            }
         }
 
         AU_LOCK_GUARD(this->workersMutex);
diff --git a/Source/Async/AuGroupState.hpp b/Source/Async/AuGroupState.hpp
index a5e4cf5a..f85643d4 100644
--- a/Source/Async/AuGroupState.hpp
+++ b/Source/Async/AuGroupState.hpp
@@ -25,6 +25,7 @@ namespace Aurora::Async
 
         // tracked workers
         AuThreadPrimitives::Mutex workersMutex;
+        AuFutexMutex deinitMutex;
         AuBST<ThreadId_t, AuSPtr<ThreadState>> workers;
         AuWPtr<ThreadState> wpWorkers[32]; // linear non-locking lookup table
         //
diff --git a/Source/Async/ThreadPool.cpp b/Source/Async/ThreadPool.cpp
index cf38b5e4..4be07c09 100644
--- a/Source/Async/ThreadPool.cpp
+++ b/Source/Async/ThreadPool.cpp
@@ -176,7 +176,6 @@ namespace Aurora::Async
 
     size_t ThreadPool::GetThreadWorkersCount(ThreadGroup_t group)
     {
-        AU_LOCK_GUARD(this->pRWReadView);
         return GetGroup(group)->workers.size();
     }
 
@@ -706,8 +705,6 @@ namespace Aurora::Async
     
     AuBST<ThreadGroup_t, AuList<ThreadId_t>> ThreadPool::GetThreads()
     {
-        AU_LOCK_GUARD(this->pRWReadView);
-
         AuBST<ThreadGroup_t, AuList<ThreadId_t>> ret;
 
         for (auto pGroup : this->threadGroups_)
@@ -719,6 +716,7 @@ namespace Aurora::Async
                 continue;
             }
 
+            AU_LOCK_GUARD(pGroup->workersMutex);
             AuTryReserve(workers, pGroup->workers.size());
 
             for (const auto &thread : pGroup->workers)
@@ -764,11 +762,10 @@ namespace Aurora::Async
     
     void ThreadPool::Signal(WorkerId_t workerId)
     {
-        AU_LOCK_GUARD(this->pRWReadView);
-
         auto group = GetGroup(workerId.first);
         if (workerId.second == Async::kThreadIdAny)
         {
+            AU_LOCK_GUARD(group->workersMutex);
             for (auto &jobWorker : group->workers)
             {
                 jobWorker.second->running->Set();
@@ -782,8 +779,6 @@ namespace Aurora::Async
 
     AuSPtr<AuLoop::ILoopSource> ThreadPool::WorkerToLoopSource(WorkerId_t workerId)
     {
-        AU_LOCK_GUARD(this->pRWReadView);
-
         auto a = GetThreadHandle(workerId);
         if (!a)
         {
@@ -1288,7 +1283,6 @@ namespace Aurora::Async
         }
 
         {
-            AU_LOCK_GUARD(this->rwlock_->AsWritable());
             state->Decommit(id.second);
         }
     }
@@ -1361,8 +1355,6 @@ namespace Aurora::Async
 
     AuList<AuSPtr<ThreadState>> ThreadPool::GetThreadHandles(WorkerId_t id)
     {
-        AU_LOCK_GUARD(this->pRWReadView);
-
         auto group = GetGroup(id.first);
         if (!group)
         {
@@ -1379,6 +1371,7 @@ namespace Aurora::Async
         }
         else
         {
+            AU_LOCK_GUARD(group->workersMutex);
             for (const auto &[key, value] : group->workers)
             {
                 ret.push_back(value);