diff --git a/src/core/roctracer.cpp b/src/core/roctracer.cpp
index 8d3f984118..94c19a36b3 100644
--- a/src/core/roctracer.cpp
+++ b/src/core/roctracer.cpp
@@ -1198,8 +1198,6 @@ PUBLIC_API roctracer_status_t roctracer_set_properties(
   API_METHOD_PREFIX
   switch (domain) {
     case ACTIVITY_DOMAIN_HSA_OPS: {
-      roctracer::trace_buffer.StartWorkerThread();
-
       // HSA OPS properties
       roctracer::hsa_ops_properties_t* ops_properties = reinterpret_cast<roctracer::hsa_ops_properties_t*>(properties);
       HsaApiTable* table = reinterpret_cast<HsaApiTable*>(ops_properties->table);
diff --git a/src/core/trace_buffer.h b/src/core/trace_buffer.h
index fc778bb95e..c36c012014 100644
--- a/src/core/trace_buffer.h
+++ b/src/core/trace_buffer.h
@@ -231,7 +231,7 @@ class TraceBuffer : protected TraceBufferBase {
 
   void wrap_buffer(const pointer_t pointer) {
     std::lock_guard<mutex_t> lck(mutex_);
-    if (work_thread_started_ == false) FATAL("worker thread is not started");
+    if (work_thread_started_ == false) StartWorkerThread();
 
     PTHREAD_CALL(pthread_mutex_lock(&work_mutex_));
     if (pointer >= end_pointer_) {
diff --git a/test/tool/tracer_tool.cpp b/test/tool/tracer_tool.cpp
index 9908947955..65ff06ebfd 100644
--- a/test/tool/tracer_tool.cpp
+++ b/test/tool/tracer_tool.cpp
@@ -49,6 +49,17 @@ THE SOFTWARE.
 #define CONSTRUCTOR_API __attribute__((constructor))
 #define DESTRUCTOR_API __attribute__((destructor))
 
+// Linux sys call
+#define PTHREAD_CALL(call)                                                                         \
+  do {                                                                                             \
+    int err = call;                                                                                \
+    if (err != 0) {                                                                                \
+      errno = err;                                                                                 \
+      perror(#call);                                                                               \
+      abort();                                                                                     \
+    }                                                                                              \
+  } while (0)
+
 // Macro to check ROC-tracer calls status
 #define ROCTRACER_CALL(call)                                                                       \
   do {                                                                                             \
@@ -158,6 +169,10 @@ void* control_thr_fun(void*) {
 
 // Flushing control thread
 uint32_t control_flush_us = 0;
+pthread_t flush_thread;
+bool flush_thread_started = false;
+std::mutex flush_thread_mutex;;
+
 void* flush_thr_fun(void*) {
   const uint32_t dist_sec = control_flush_us / 1000000;
   const uint32_t dist_us = control_flush_us % 1000000;
@@ -165,9 +180,13 @@ void* flush_thr_fun(void*) {
   while (1) {
     sleep(dist_sec);
     usleep(dist_us);
-    roctracer_flush_activity();
+    std::lock_guard<std::mutex> lock(flush_thread_mutex);
+    if (!flush_thread_started) while(1) sleep(1);
+    ROCTRACER_CALL(roctracer_flush_activity());
     roctracer::TraceBufferBase::FlushAll();
   }
+
+  return NULL;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -616,6 +635,16 @@ void tool_unload() {
   if (is_loaded == false) return;
   is_loaded = false;
 
+  if (flush_thread_started) {
+    flush_thread_mutex.lock();
+    flush_thread_started = false;
+    flush_thread_mutex.unlock();
+    PTHREAD_CALL(pthread_cancel(flush_thread));
+    void *res;
+    PTHREAD_CALL(pthread_join(flush_thread, &res));
+    if (res != PTHREAD_CANCELED) FATAL("flush thread wasn't stopped correctly");
+  }
+
   if (trace_roctx) {
     ROCTRACER_CALL(roctracer_disable_domain_callback(ACTIVITY_DOMAIN_ROCTX));
   }
@@ -649,8 +678,6 @@ void tool_load() {
   if (is_loaded == true) return;
   is_loaded = true;
 
-  roctracer::TraceBufferBase::StartWorkerThreadAll();
-
   // Output file
   const char* output_prefix = getenv("ROCP_OUTPUT_DIR");
   if (output_prefix != NULL) {
@@ -807,11 +834,12 @@ void tool_load() {
     }
 
     fprintf(stdout, "ROCTracer: trace control flush rate(%uus)\n", control_flush_us); fflush(stdout);
-    pthread_t thread;
     pthread_attr_t attr;
     int err = pthread_attr_init(&attr);
     if (err) { errno = err; perror("pthread_attr_init"); abort(); }
-    err = pthread_create(&thread, &attr, flush_thr_fun, NULL);
+    std::lock_guard<std::mutex> lock(flush_thread_mutex);
+    PTHREAD_CALL(pthread_create(&flush_thread, &attr, flush_thr_fun, NULL));
+    flush_thread_started = true;
   }
 
   // Enable KFD API callbacks/activity