diff --git a/src/hotspot/share/prims/jni.cpp b/src/hotspot/share/prims/jni.cpp
index 4787247d722..48dcb9a88ff 100644
--- a/src/hotspot/share/prims/jni.cpp
+++ b/src/hotspot/share/prims/jni.cpp
@@ -625,6 +625,7 @@ JNI_ENTRY(void, jni_FatalError(JNIEnv *env, const char *msg))
 
   tty->print_cr("FATAL ERROR in native method: %s", msg);
   thread->print_jni_stack();
+  assert(false, "crash in JNI");
   os::abort(); // Dump core and abort
 JNI_END
 
diff --git a/src/hotspot/share/prims/jvmtiEnv.cpp b/src/hotspot/share/prims/jvmtiEnv.cpp
index 554b4baf7b2..6a870fa7ce6 100644
--- a/src/hotspot/share/prims/jvmtiEnv.cpp
+++ b/src/hotspot/share/prims/jvmtiEnv.cpp
@@ -602,6 +602,10 @@ JvmtiEnv::SetEventNotificationMode(jvmtiEventMode mode, jvmtiEvent event_type, j
     }
 
     JvmtiEventController::set_user_enabled(this, java_thread, thread_obj, event_type, enabled);
+
+    if (enabled && java_thread != nullptr && java_thread->log_jvmti()) {
+      os::naked_short_sleep(20);
+    }
   }
 
   return JVMTI_ERROR_NONE;
diff --git a/src/hotspot/share/prims/jvmtiExport.cpp b/src/hotspot/share/prims/jvmtiExport.cpp
index c68692a2fa1..84bf0881f55 100644
--- a/src/hotspot/share/prims/jvmtiExport.cpp
+++ b/src/hotspot/share/prims/jvmtiExport.cpp
@@ -1332,7 +1332,12 @@ void JvmtiExport::at_single_stepping_point(JavaThread *thread, Method* method, a
   methodHandle mh(thread, method);
 
   // update information about current location and post a step event
+  thread->set_log_jvmti(true);
+  if (!thread->is_in_VTMS_transition()) {
+    os::naked_short_sleep(20);
+  }
   JvmtiThreadState *state = get_jvmti_thread_state(thread);
+  thread->set_log_jvmti(false);
   if (state == nullptr) {
     return;
   }
@@ -1345,6 +1350,9 @@ void JvmtiExport::at_single_stepping_point(JavaThread *thread, Method* method, a
     if (state->is_pending_step_for_earlyret()) {
       state->process_pending_step_for_earlyret();
     }
+    if (thread->is_suspended()) {
+      os::naked_short_sleep(10);
+    }
     JvmtiExport::post_single_step(thread, mh(), location);
   }
 }
diff --git a/src/hotspot/share/runtime/javaThread.cpp b/src/hotspot/share/runtime/javaThread.cpp
index 86aa62fd3fb..096607a044e 100644
--- a/src/hotspot/share/runtime/javaThread.cpp
+++ b/src/hotspot/share/runtime/javaThread.cpp
@@ -462,6 +462,8 @@ JavaThread::JavaThread(MemTag mem_tag) :
   _is_VTMS_transition_disabler(false),
 #endif
 #endif
+  _log_jvmti(false),
+
   _jni_attach_state(_not_attaching_via_jni),
   _is_in_internal_oome_mark(false),
 #if INCLUDE_JVMCI
diff --git a/src/hotspot/share/runtime/javaThread.hpp b/src/hotspot/share/runtime/javaThread.hpp
index 9a74a6248d0..55d8ea0222e 100644
--- a/src/hotspot/share/runtime/javaThread.hpp
+++ b/src/hotspot/share/runtime/javaThread.hpp
@@ -335,6 +335,12 @@ class JavaThread: public Thread {
 #endif
 #endif
 
+ public:
+  bool                  _log_jvmti;
+  bool log_jvmti()             { return _log_jvmti; }
+  void set_log_jvmti(bool val) { _log_jvmti = val; }
+
+ private:
   // JNI attach states:
   enum JNIAttachStates {
     _not_attaching_via_jni = 1,  // thread is not attaching via JNI
diff --git a/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/GetStackTraceSuspendedStressTest.java b/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/GetStackTraceSuspendedStressTest.java
index fb0945678db..bc4dc99e6a1 100644
--- a/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/GetStackTraceSuspendedStressTest.java
+++ b/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/GetStackTraceSuspendedStressTest.java
@@ -39,7 +39,7 @@
     private static final String agentLib = "GetStackTraceSuspendedStress";
 
     static final int MSG_COUNT = 1000;
-    static final int VTHREAD_COUNT = 60;
+    static final int VTHREAD_COUNT = 1000;
     static final SynchronousQueue<String> QUEUE = new SynchronousQueue<>();
 
     static void producer(String msg) throws InterruptedException {
diff --git a/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/libGetStackTraceSuspendedStress.cpp b/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/libGetStackTraceSuspendedStress.cpp
index 037448a6428..258ff48a244 100644
--- a/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/libGetStackTraceSuspendedStress.cpp
+++ b/test/hotspot/jtreg/serviceability/jvmti/stress/StackTrace/Suspended/libGetStackTraceSuspendedStress.cpp
@@ -192,7 +192,7 @@ agentProc(jvmtiEnv * jvmti, JNIEnv * jni, void * arg) {
         return;
       }
       check_jvmti_status(jni, err,  "Error in GetVirtualThread");
-      if (iter > 50 && vthread != nullptr) {
+      if (vthread != nullptr) {
         // char* cname = get_thread_name(jvmti, jni, cthread);
         // char* vname = get_thread_name(jvmti, jni, vthread);
 
@@ -214,7 +214,7 @@ agentProc(jvmtiEnv * jvmti, JNIEnv * jni, void * arg) {
   //check_jvmti_status(jni, jvmti->Deallocate((unsigned char *) vname), "Error in Deallocate");
 
     iter++;
-    sleep_ms(20);
+    //sleep_ms(20);
   }
   LOG("Agent: finished\n");
 }