From 94f2107df113982d58cda32260c8ff73c442b829 Mon Sep 17 00:00:00 2001
From: heck <heck@pep.foundation>
Date: Tue, 21 Apr 2020 00:05:12 +0200
Subject: [PATCH] Acquire global mutex to obtain mutex for java obj update
 stress test jni92, add option useSharedEngines

---
 src/basic_api.cc                              | 135 ++++++++++++++----
 ...oundation_pEp_jniadapter_AbstractEngine.cc | 105 +++++++++-----
 src/gen_cpp_Engine.ysl2                       |   9 +-
 src/jniutils.cc                               |   3 +-
 .../pEp/jniadapter/test/jni92/TestMain.java   |  36 +++--
 .../pEp/jniadapter/test/utils/TestUtils.java  |  20 ++-
 6 files changed, 226 insertions(+), 82 deletions(-)

diff --git a/src/basic_api.cc b/src/basic_api.cc
index f776eab..d16553b 100644
--- a/src/basic_api.cc
+++ b/src/basic_api.cc
@@ -19,8 +19,13 @@ JNIEXPORT jbyteArray JNICALL Java_foundation_pEp_jniadapter_Engine_trustwords(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
     char *words;
@@ -59,8 +64,13 @@ JNIEXPORT jobject JNICALL Java_foundation_pEp_jniadapter_Engine_myself(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -80,8 +90,13 @@ JNIEXPORT jobject JNICALL Java_foundation_pEp_jniadapter_Engine_updateIdentity(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -97,8 +112,13 @@ JNIEXPORT jobject JNICALL Java_foundation_pEp_jniadapter_Engine_setOwnKey(
         jbyteArray fpr
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
     char *_fpr = to_string(env, fpr);
@@ -120,8 +140,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_keyMistrusted(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -146,8 +171,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_keyResetTrust(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -172,8 +202,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_trustPersonalKey(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -198,8 +233,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_trustOwnKey(
         jobject ident
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEp_identity *_ident = to_identity(env, ident);
 
@@ -217,8 +257,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_importKey(
         jbyteArray key
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     size_t _size = (size_t) env->GetArrayLength(key);
     char *_key = (char *) env->GetByteArrayElements(key, NULL);
@@ -243,8 +288,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_config_1passive_1mo
         jboolean enable
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     ::config_passive_mode(session(), (bool)enable);
 }
@@ -256,8 +306,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_config_1unencrypted
         jboolean enable
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     ::config_unencrypted_subject(session(), (bool)enable);
 }
@@ -268,8 +323,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_blacklist_1add(
         jbyteArray fpr
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     char *_fpr = to_string(env, fpr);
 
@@ -292,8 +352,13 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_Engine_blacklist_1delete(
         jbyteArray fpr
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     char *_fpr = to_string(env, fpr);
 
@@ -316,8 +381,13 @@ JNIEXPORT jboolean JNICALL Java_foundation_pEp_jniadapter_Engine_blacklist_1is_1
         jbyteArray fpr
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     char *_fpr = to_string(env, fpr);
     bool _listed = 0;
@@ -343,8 +413,13 @@ JNIEXPORT jbyteArray JNICALL Java_foundation_pEp_jniadapter_Engine_getCrashdumpL
         jint maxlines
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     int _maxlines = (int) maxlines;
     char *_logdata;
diff --git a/src/foundation_pEp_jniadapter_AbstractEngine.cc b/src/foundation_pEp_jniadapter_AbstractEngine.cc
index 0ed33d8..40d4e03 100644
--- a/src/foundation_pEp_jniadapter_AbstractEngine.cc
+++ b/src/foundation_pEp_jniadapter_AbstractEngine.cc
@@ -172,54 +172,64 @@ using namespace pEp;
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_init(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called");
     std::lock_guard<std::mutex> l(global_mutex); // global mutex for write access to <unordered_map>
+    pEpLog("called");
 
     if (first) {
         pEpLog("first Engine instance");
         first = false;
         env->GetJavaVM(&jvm);
         jni_init();
-        objj = env->NewGlobalRef(me);
+        objj = env->NewGlobalRef(obj);
         Adapter::_messageToSend = messageToSend;
     }
 
-    create_engine_java_object_mutex(env, me);  // Create a mutex per java object
+    create_engine_java_object_mutex(env, obj);  // Create a mutex per java object
     Adapter::session();
 }
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_release(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called");
     std::lock_guard<std::mutex> l(global_mutex);  // global mutex for write access to <unordered_map>
-    release_engine_java_object_mutex(env, me);
+    pEpLog("called");
+    release_engine_java_object_mutex(env, obj);
     Adapter::session(pEp::Adapter::release);
 }
 
 JNIEXPORT jstring JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_getVersion(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     return env->NewStringUTF(::get_engine_version());
 }
 
 JNIEXPORT jstring JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_getProtocolVersion(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     return env->NewStringUTF(::get_protocol_version());
 }
@@ -263,11 +273,16 @@ static void *keyserver_thread_routine(void *arg)
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_startKeyserverLookup(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pthread_t *thread = nullptr;
     locked_queue< pEp_identity * > *queue = nullptr;
@@ -284,16 +299,16 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_startKeyser
         return;
     }
 
-    thread = (pthread_t *) env->GetLongField(me, thread_handle);
+    thread = (pthread_t *) env->GetLongField(obj, thread_handle);
     if (thread)
         return;
 
     thread = (pthread_t *) calloc(1, sizeof(pthread_t));
     assert(thread);
-    env->SetLongField(me, thread_handle, (jlong) thread);
+    env->SetLongField(obj, thread_handle, (jlong) thread);
 
     queue = new locked_queue< pEp_identity * >();
-    env->SetLongField(me, queue_handle, (jlong) queue);
+    env->SetLongField(obj, queue_handle, (jlong) queue);
 
     register_examine_function(Adapter::session(), examine_identity, (void *) queue);
 
@@ -302,11 +317,16 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_startKeyser
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_stopKeyserverLookup(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pthread_t *thread = nullptr;
     locked_queue< pEp_identity * > *queue = nullptr;
@@ -323,14 +343,14 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_stopKeyserv
         return;
     }
 
-    thread = (pthread_t *) env->GetLongField(me, thread_handle);
+    thread = (pthread_t *) env->GetLongField(obj, thread_handle);
     if (!thread)
         return;
 
-    queue = (locked_queue< pEp_identity * > *) env->GetLongField(me, queue_handle);
+    queue = (locked_queue< pEp_identity * > *) env->GetLongField(obj, queue_handle);
 
-    env->SetLongField(me, queue_handle, (jlong) 0);
-    env->SetLongField(me, thread_handle, (jlong) 0);
+    env->SetLongField(obj, queue_handle, (jlong) 0);
+    env->SetLongField(obj, thread_handle, (jlong) 0);
 
     register_examine_function(Adapter::session(), nullptr, nullptr);
 
@@ -341,11 +361,16 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_stopKeyserv
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_startSync(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     pEpLog("######## starting sync");
     try {
@@ -359,22 +384,32 @@ JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_startSync(
 
 JNIEXPORT void JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_stopSync(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     Adapter::shutdown();
 }
 
 JNIEXPORT jboolean JNICALL Java_foundation_pEp_jniadapter_AbstractEngine_isSyncRunning(
         JNIEnv *env,
-        jobject me
+        jobject obj
     )
 {
-    pEpLog("called with lock_guard");
-    std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, me));
+    std::mutex *mutex_local = nullptr;
+    {
+        std::lock_guard<std::mutex> l(global_mutex);
+        pEpLog("called with lock_guard");
+        mutex_local = get_engine_java_object_mutex(env, obj);
+    }
+    std::lock_guard<std::mutex> l(*mutex_local);
 
     return (jboolean) Adapter::is_sync_running();
 }
diff --git a/src/gen_cpp_Engine.ysl2 b/src/gen_cpp_Engine.ysl2
index 853d4b0..3fb0e1c 100644
--- a/src/gen_cpp_Engine.ysl2
+++ b/src/gen_cpp_Engine.ysl2
@@ -47,8 +47,13 @@ tstylesheet {
                 jobject obj`apply "parm[in|inout]", mode=sig`
             )
         {
-            pEpLog("called with lock_guard");
-            std::lock_guard<std::mutex> l(*get_engine_java_object_mutex(env, obj));
+            std::mutex *mutex_local = nullptr;
+            {
+                std::lock_guard<std::mutex> l(global_mutex);
+                pEpLog("called with lock_guard");
+                mutex_local = get_engine_java_object_mutex(env, obj);
+            }
+            std::lock_guard<std::mutex> l(*mutex_local);
 
         ||
 
diff --git a/src/jniutils.cc b/src/jniutils.cc
index 0ca7b4d..e4d2820 100644
--- a/src/jniutils.cc
+++ b/src/jniutils.cc
@@ -21,8 +21,9 @@ namespace pEp {
         {
             long engine_obj_id = (long)callLongMethod(env, obj, "getId");
             assert(engine_obj_id);
+            pEpLog("for java object id: " << engine_obj_id);
             std::mutex *engine_obj_mutex = engine_objid_mutex.at(engine_obj_id);
-            pEpLog(engine_obj_mutex << " with native_handle: " << engine_obj_mutex->native_handle() << " for java object id: " << engine_obj_id);
+            pEpLog("found mutex: " << engine_obj_mutex << " with native_handle: " << engine_obj_mutex->native_handle());
             assert(engine_obj_mutex);
             return engine_obj_mutex;
         }
diff --git a/test/java/foundation/pEp/jniadapter/test/jni92/TestMain.java b/test/java/foundation/pEp/jniadapter/test/jni92/TestMain.java
index a7b8cd5..a646590 100644
--- a/test/java/foundation/pEp/jniadapter/test/jni92/TestMain.java
+++ b/test/java/foundation/pEp/jniadapter/test/jni92/TestMain.java
@@ -16,19 +16,23 @@ https://pep.foundation/jira/browse/JNI-81
 
 class TestThread extends Thread {
     int nrEngines = 1;
-    TestThread(String threadName, int nrEngines) {
+    boolean useSharedEngines = false;
+    TestThread(String threadName, int nrEngines, boolean useSharedEngines) {
         Thread.currentThread().setName(threadName);
         this.nrEngines = nrEngines;
+        this.useSharedEngines = useSharedEngines;
     }
 
     public void run() {
         TestUtils.logH1( "Thread Starting");
-        TestMain.TestMainRun(nrEngines);
+        TestMain.TestMainRun(nrEngines, useSharedEngines);
     }
 }
 
 
 class TestMain {
+    static Vector<Engine> sharedEngines;
+
     public static Engine createNewEngine() throws pEpException {
         Engine e;
         TestUtils.logH2("Creating new Engine");
@@ -52,8 +56,7 @@ class TestMain {
         });
     }
 
-    public static void TestMainRun(int nrEngines) {
-        Vector<Engine> engineVector = TestMain.createEngines(nrEngines);
+    public static void TestMainRun(int nrEngines, boolean useSharedEngines) {
         Consumer<Engine> c = (e) -> {
            Vector<Identity> v = e.own_identities_retrieve();
 
@@ -64,27 +67,38 @@ class TestMain {
             e.getVersion();
             e.OpenPGP_list_keyinfo("");
         };
-        TestMain.engineConsumer(engineVector, c);
+
+        if(useSharedEngines) {
+            TestMain.engineConsumer(sharedEngines, c);
+        } else {
+            Vector<Engine> threadLocalEngines = TestMain.createEngines(nrEngines);
+            TestMain.engineConsumer(threadLocalEngines, c);
+        }
     }
 
     public static void main(String[] args) {
         TestUtils.logH1("JNI-92 Starting");
-
-        int nrTestruns = 100;
+        TestUtils.setLoggingEnabled(false);
+        int nrTestruns = 1000;
         boolean multiThreaded = true;
-        int nrThreads = 200;
-        int nrEnginesPerThread = 100;
+        boolean useSharedEngines = true;
+        int nrThreads = 100;
+        int nrEnginesPerThread = 1;
+
+        if(useSharedEngines) {
+            sharedEngines = TestMain.createEngines(nrEnginesPerThread);
+        }
 
         for (int run = 0; run < nrTestruns; run++ ) {
             TestUtils.logH1("Testrun Nr: " + run);
             if (!multiThreaded) {
                 // Single Threaded
-                TestMainRun(nrEnginesPerThread);
+                TestMainRun(nrEnginesPerThread, useSharedEngines);
             } else {
                 // Mutli Threaded
                 Vector<TestThread> tts = new Vector<TestThread>();
                 for (int i = 0; i < nrThreads; i++) {
-                    tts.add(new TestThread("TestThread-" + i, nrEnginesPerThread));
+                    tts.add(new TestThread("TestThread-" + i, nrEnginesPerThread, useSharedEngines));
                 }
 
                 tts.forEach(t -> {
diff --git a/test/java/foundation/pEp/jniadapter/test/utils/TestUtils.java b/test/java/foundation/pEp/jniadapter/test/utils/TestUtils.java
index 83d7d75..3833b18 100644
--- a/test/java/foundation/pEp/jniadapter/test/utils/TestUtils.java
+++ b/test/java/foundation/pEp/jniadapter/test/utils/TestUtils.java
@@ -22,10 +22,24 @@ public class TestUtils {
         return ret;
     }
 
+    // ------------------------ Logging ------------------------
+
+    private static boolean logEnabled = true;
+
+    public static void setLoggingEnabled(boolean enabled) {
+        logEnabled = enabled;
+    }
+
+    public static boolean isLoggingEnabled() {
+        return logEnabled;
+    }
+
     public static void log(String msg) {
-        String threadNameFmt = String.format("%-10s", Thread.currentThread().getName());
-        String msgOut = threadNameFmt + ": " + msg;
-        System.out.println(msgOut);
+        if(logEnabled) {
+            String threadNameFmt = String.format("%-10s", Thread.currentThread().getName());
+            String msgOut = threadNameFmt + ": " + msg;
+            System.out.println(msgOut);
+        }
     }
 
     public static void logH1(String msg) {