diff --git a/.github/workflows/functionsTests.yml b/.github/workflows/functionsTests.yml
index 63fd85e..7d0349a 100644
--- a/.github/workflows/functionsTests.yml
+++ b/.github/workflows/functionsTests.yml
@@ -54,7 +54,8 @@
           data.rand,
           data.tensor,
           dnn,
-          federated,
+          federated.algorithms,
+          federated.primitives,
           frame,
           indexing,
           io,
diff --git a/src/main/java/org/apache/sysds/runtime/controlprogram/federated/FederatedWorkerHandler.java b/src/main/java/org/apache/sysds/runtime/controlprogram/federated/FederatedWorkerHandler.java
index 0dcb846..b09b75d 100644
--- a/src/main/java/org/apache/sysds/runtime/controlprogram/federated/FederatedWorkerHandler.java
+++ b/src/main/java/org/apache/sysds/runtime/controlprogram/federated/FederatedWorkerHandler.java
@@ -19,14 +19,14 @@
 
 package org.apache.sysds.runtime.controlprogram.federated;
 
-import io.netty.channel.ChannelFuture;
-import io.netty.channel.ChannelFutureListener;
-import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.Arrays;
 
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.log4j.Logger;
+import org.apache.sysds.api.DMLScript;
 import org.apache.sysds.common.Types;
 import org.apache.sysds.common.Types.DataType;
 import org.apache.sysds.common.Types.FileFormat;
@@ -52,11 +52,13 @@
 import org.apache.sysds.runtime.privacy.PrivacyMonitor;
 import org.apache.sysds.runtime.privacy.PrivacyPropagator;
 import org.apache.sysds.utils.JSONHelper;
+import org.apache.sysds.utils.Statistics;
 import org.apache.wink.json4j.JSONObject;
 
-import java.io.BufferedReader;
-import java.io.InputStreamReader;
-import java.util.Arrays;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
 
 public class FederatedWorkerHandler extends ChannelInboundHandlerAdapter {
 	protected static Logger log = Logger.getLogger(FederatedWorkerHandler.class);
@@ -110,6 +112,11 @@
 			else if( response == null && i == requests.length-1 ) {
 				response = tmp; //return last
 			}
+
+			if (DMLScript.STATISTICS && request.getType() == RequestType.CLEAR){
+				System.out.println("Federated Worker " + Statistics.display());
+				Statistics.reset();
+			}
 		}
 		ctx.writeAndFlush(response).addListener(new CloseListener());
 	}
diff --git a/src/main/java/org/apache/sysds/utils/Statistics.java b/src/main/java/org/apache/sysds/utils/Statistics.java
index b498b0e..8f22ab4 100644
--- a/src/main/java/org/apache/sysds/utils/Statistics.java
+++ b/src/main/java/org/apache/sysds/utils/Statistics.java
@@ -501,6 +501,11 @@
 		nativeConv2dBwdFilterTime = 0;
 		nativeConv2dBwdDataTime = 0;
 		LibMatrixDNN.resetStatistics();
+		federatedReadCount.reset();
+		federatedPutCount.reset();
+		federatedGetCount.reset();
+		federatedExecuteInstructionCount.reset();
+		federatedExecuteUDFCount.reset();
 	}
 
 	public static void resetJITCompileTime(){
diff --git a/src/test/java/org/apache/sysds/test/AutomatedTestBase.java b/src/test/java/org/apache/sysds/test/AutomatedTestBase.java
index bfb2e5d..7bca262 100644
--- a/src/test/java/org/apache/sysds/test/AutomatedTestBase.java
+++ b/src/test/java/org/apache/sysds/test/AutomatedTestBase.java
@@ -19,6 +19,7 @@
 
 package org.apache.sysds.test;
 
+import static java.lang.Thread.sleep;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
 
@@ -100,7 +101,7 @@
 	public static final boolean TEST_GPU = false;
 	public static final double GPU_TOLERANCE = 1e-9;
 
-	public static final int FED_WORKER_WAIT = 750; // in ms
+	public static final int FED_WORKER_WAIT = 1000; // in ms
 
 	// With OpenJDK 8u242 on Windows, the new changes in JDK are not allowing
 	// to set the native library paths internally thus breaking the code.
@@ -1283,38 +1284,40 @@
 		}
 	}
 
-	protected Thread startLocalFedWorker(int port) {
-		Thread t = null;
-		String[] fedWorkArgs = {"-w", Integer.toString(port)};
-		ArrayList<String> args = new ArrayList<>();
+	/**
+	 * Start new JVM for a federated worker at the port.
+	 * 
+	 * 
+	 * @param port Port to use for the JVM
+	 * @return the process associated with the worker.
+	 */
+	protected Process startLocalFedWorker(int port) {
+		Process process = null;
+		String separator = System.getProperty("file.separator");
+		String classpath = System.getProperty("java.class.path");
+		String path = System.getProperty("java.home")
+					+ separator + "bin" + separator + "java";
+		ProcessBuilder processBuilder = new ProcessBuilder(path, "-cp", 
+				classpath, DMLScript.class.getName(), "-w",  Integer.toString(port), "-stats");
 
-		addProgramIndependentArguments(args);
-
-		for(int i = 0; i < fedWorkArgs.length; i++)
-			args.add(fedWorkArgs[i]);
-
-		String[] finalArguments = args.toArray(new String[args.size()]);
-
-		try {
-			t = new Thread(() -> {
-				try {
-					main(finalArguments);
-				}
-				catch(IOException e) {
-				}
-			});
-			t.start();
-			java.util.concurrent.TimeUnit.MILLISECONDS.sleep(FED_WORKER_WAIT);
+		try{
+			process = processBuilder.start();
+			// Give some time to startup the worker.
+			sleep(FED_WORKER_WAIT);
+		} catch (IOException | InterruptedException e){
+			e.printStackTrace();
 		}
-		catch(InterruptedException e) {
-			// Should happen at closing of the worker so don't print
-		}
-		return t;
+		return process;
 	}
 
+	/**
+	 * Start java worker in same JVM.
+	 * @param args the command line arguments
+	 * @return the thread associated with the process.s
+	 */
 	public static Thread startLocalFedWorkerWithArgs(String[] args) {
 		Thread t = null;
-
+		
 		try {
 			t = new Thread(() -> {
 				try {
diff --git a/src/test/java/org/apache/sysds/test/TestUtils.java b/src/test/java/org/apache/sysds/test/TestUtils.java
index d5aea1c..1e38e2c 100644
--- a/src/test/java/org/apache/sysds/test/TestUtils.java
+++ b/src/test/java/org/apache/sysds/test/TestUtils.java
@@ -2469,6 +2469,11 @@
 		for( Thread t : ts )
 			shutdownThread(t);
 	}
+
+	public static void shutdownThreads(Process... ts) {
+		for( Process t : ts )
+			shutdownThread(t);
+	}
 	
 	public static void shutdownThread(Thread t) {
 		// kill the worker
@@ -2482,6 +2487,19 @@
 			}
 		}
 	}
+
+	public static void shutdownThread(Process t) {
+		// kill the worker
+		if( t != null ) {
+			Process d = t.destroyForcibly();
+			try {
+				d.waitFor();
+			}
+			catch (InterruptedException e) {
+				e.printStackTrace();
+			}
+		}
+	}
 	
 	public static String federatedAddress(int port, String input) {
 		return federatedAddress("localhost", port, input);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBivarTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedBivarTest.java
similarity index 96%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedBivarTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedBivarTest.java
index 906beec..96fef5d 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBivarTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedBivarTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.apache.sysds.common.Types;
 import org.apache.sysds.runtime.meta.MatrixCharacteristics;
@@ -116,10 +116,10 @@
 		int port2 = getRandomAvailablePort();
 		int port3 = getRandomAvailablePort();
 		int port4 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
-		Thread t3 = startLocalFedWorker(port3);
-		Thread t4 = startLocalFedWorker(port4);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
+		Process t3 = startLocalFedWorker(port3);
+		Process t4 = startLocalFedWorker(port4);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedGLMTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedGLMTest.java
similarity index 96%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedGLMTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedGLMTest.java
index 009d921..636b279 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedGLMTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedGLMTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -94,8 +94,8 @@
 		fullDMLScriptName = "";
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedKmeansTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedKmeansTest.java
similarity index 97%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedKmeansTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedKmeansTest.java
index 7b60476..933e971 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedKmeansTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedKmeansTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -101,8 +101,8 @@
 		fullDMLScriptName = "";
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedL2SVMTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedL2SVMTest.java
similarity index 98%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedL2SVMTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedL2SVMTest.java
index 4cfc70e..4caf52e 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedL2SVMTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedL2SVMTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -76,7 +76,7 @@
 		if(rtplatform == Types.ExecMode.SPARK) {
 			DMLScript.USE_LOCAL_SPARK_CONFIG = true;
 		}
-		Thread t1, t2;
+		Process t1, t2;
 
 		getAndLoadTestConfiguration(TEST_NAME);
 		String HOME = SCRIPT_DIR + TEST_DIR;
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedLogRegTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedLogRegTest.java
similarity index 75%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedLogRegTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedLogRegTest.java
index 1c07bfc..fef8889 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedLogRegTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedLogRegTest.java
@@ -17,12 +17,13 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
-import org.junit.Assert;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.Parameterized;
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.Collection;
+
 import org.apache.sysds.common.Types;
 import org.apache.sysds.common.Types.ExecMode;
 import org.apache.sysds.runtime.meta.MatrixCharacteristics;
@@ -30,9 +31,10 @@
 import org.apache.sysds.test.AutomatedTestBase;
 import org.apache.sysds.test.TestConfiguration;
 import org.apache.sysds.test.TestUtils;
-
-import java.util.Arrays;
-import java.util.Collection;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
 
 @RunWith(value = Parameterized.class)
 @net.jcip.annotations.NotThreadSafe
@@ -61,17 +63,16 @@
 	}
 
 	@Test
-	public void federatedSinglenodeGLM() {
-		federatedGLM(Types.ExecMode.SINGLE_NODE);
+	public void federatedSinglenodeLogReg() {
+		federatedLogReg(Types.ExecMode.SINGLE_NODE);
 	}
 
 	@Test
-	public void federatedHybridGLM() {
-		federatedGLM(Types.ExecMode.HYBRID);
+	public void federatedHybridLogReg() {
+		federatedLogReg(Types.ExecMode.HYBRID);
 	}
 
-	
-	public void federatedGLM(Types.ExecMode execMode) {
+	public void federatedLogReg(Types.ExecMode execMode) {
 		ExecMode platformOld = setExecMode(execMode);
 
 		getAndLoadTestConfiguration(TEST_NAME);
@@ -94,13 +95,25 @@
 		fullDMLScriptName = "";
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
+
+		BufferedReader output = new BufferedReader(new InputStreamReader(t1.getInputStream()));
+		BufferedReader error = new BufferedReader(new InputStreamReader(t1.getInputStream()));
+
+		Thread t = new Thread(() -> {
+			output.lines().forEach(s -> System.out.println(s));
+		});
+		Thread te = new Thread(() -> {
+			error.lines().forEach(s -> System.err.println(s));
+		});
+		t.start();
+		te.start();
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
 		setOutputBuffering(false);
-		
+
 		// Run reference dml script with normal matrix
 		fullDMLScriptName = HOME + TEST_NAME + "Reference.dml";
 		programArgs = new String[] {"-args", input("X1"), input("X2"), input("Y"), expected("Z")};
@@ -108,8 +121,8 @@
 
 		// Run actual dml script with federated matrix
 		fullDMLScriptName = HOME + TEST_NAME + ".dml";
-		programArgs = new String[] {"-stats", "30",
-			"-nvargs", "in_X1=" + TestUtils.federatedAddress(port1, input("X1")),
+		programArgs = new String[] {"-stats", "30", "-nvargs",
+			"in_X1=" + TestUtils.federatedAddress(port1, input("X1")),
 			"in_X2=" + TestUtils.federatedAddress(port2, input("X2")), "rows=" + rows, "cols=" + cols,
 			"in_Y=" + input("Y"), "out=" + output("Z")};
 		runTest(true, false, null, -1);
@@ -118,16 +131,19 @@
 		compareResults(1e-9);
 
 		TestUtils.shutdownThreads(t1, t2);
+		TestUtils.shutdownThreads(t, te);
 
 		// check for federated operations
-		Assert.assertTrue("contains federated matrix mult",heavyHittersContainsString("fed_ba+*"));
-		Assert.assertTrue("contains federated row unary aggregate",heavyHittersContainsString("fed_uark+","fed_uarsqk+"));
-		Assert.assertTrue("contains federated matrix mult chain or transpose",heavyHittersContainsString("fed_mmchain", "fed_r'"));
-		
-		//check that federated input files are still existing
+		Assert.assertTrue("contains federated matrix mult", heavyHittersContainsString("fed_ba+*"));
+		Assert.assertTrue("contains federated row unary aggregate",
+			heavyHittersContainsString("fed_uark+", "fed_uarsqk+"));
+		Assert.assertTrue("contains federated matrix mult chain or transpose",
+			heavyHittersContainsString("fed_mmchain", "fed_r'"));
+
+		// check that federated input files are still existing
 		Assert.assertTrue(HDFSTool.existsFileOnHDFS(input("X1")));
 		Assert.assertTrue(HDFSTool.existsFileOnHDFS(input("X2")));
-		
+
 		resetExecMode(platformOld);
 	}
 }
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedPCATest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedPCATest.java
similarity index 95%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedPCATest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedPCATest.java
index 4b4457a..7a5a2fd 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedPCATest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedPCATest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -101,10 +101,10 @@
 		int port2 = getRandomAvailablePort();
 		int port3 = getRandomAvailablePort();
 		int port4 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
-		Thread t3 = startLocalFedWorker(port3);
-		Thread t4 = startLocalFedWorker(port4);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
+		Process t3 = startLocalFedWorker(port3);
+		Process t4 = startLocalFedWorker(port4);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedUnivarTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedUnivarTest.java
similarity index 95%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedUnivarTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedUnivarTest.java
index a704d3a..c042cbb 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedUnivarTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedUnivarTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.apache.sysds.common.Types;
 import org.apache.sysds.runtime.meta.MatrixCharacteristics;
@@ -101,10 +101,10 @@
 		int port2 = getRandomAvailablePort();
 		int port3 = getRandomAvailablePort();
 		int port4 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
-		Thread t3 = startLocalFedWorker(port3);
-		Thread t4 = startLocalFedWorker(port4);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
+		Process t3 = startLocalFedWorker(port3);
+		Process t4 = startLocalFedWorker(port4);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedYL2SVMTest.java b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedYL2SVMTest.java
similarity index 98%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedYL2SVMTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedYL2SVMTest.java
index 27323d8..ebdee88 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedYL2SVMTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/algorithms/FederatedYL2SVMTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.algorithms;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -78,7 +78,7 @@
 		if(rtplatform == Types.ExecMode.SPARK) {
 			DMLScript.USE_LOCAL_SPARK_CONFIG = true;
 		}
-		Thread t1, t2;
+		Process t1, t2;
 
 		getAndLoadTestConfiguration(TEST_NAME);
 		String HOME = SCRIPT_DIR + TEST_DIR;
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryMatrixTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryMatrixTest.java
similarity index 96%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryMatrixTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryMatrixTest.java
index bb8ae52..052234d 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryMatrixTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryMatrixTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -99,8 +99,8 @@
 
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryVectorTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryVectorTest.java
similarity index 96%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryVectorTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryVectorTest.java
index 0016331..187648b 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedBinaryVectorTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedBinaryVectorTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -100,8 +100,8 @@
 
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedConstructionTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedConstructionTest.java
similarity index 97%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedConstructionTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedConstructionTest.java
index 8125bfe..74180be 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedConstructionTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedConstructionTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.apache.sysds.api.DMLScript;
 import org.apache.sysds.common.Types;
@@ -120,7 +120,7 @@
 		String HOME = SCRIPT_DIR + TEST_DIR;
 
 		int port = getRandomAvailablePort();
-		Thread t = startLocalFedWorker(port);
+		Process t = startLocalFedWorker(port);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedMatrixScalarOperationsTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMatrixScalarOperationsTest.java
similarity index 98%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedMatrixScalarOperationsTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMatrixScalarOperationsTest.java
index f67bd9b..becb246 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedMatrixScalarOperationsTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMatrixScalarOperationsTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedMultiplyTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMultiplyTest.java
similarity index 96%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedMultiplyTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMultiplyTest.java
index 7968dd7..c75b0b5 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedMultiplyTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedMultiplyTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -96,8 +96,8 @@
 
 		int port1 = getRandomAvailablePort();
 		int port2 = getRandomAvailablePort();
-		Thread t1 = startLocalFedWorker(port1);
-		Thread t2 = startLocalFedWorker(port2);
+		Process t1 = startLocalFedWorker(port1);
+		Process t2 = startLocalFedWorker(port2);
 
 		TestConfiguration config = availableTestConfigurations.get(TEST_NAME);
 		loadTestConfiguration(config);
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedNegativeTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedNegativeTest.java
similarity index 97%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedNegativeTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedNegativeTest.java
index 8c60cec..5cac52c 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedNegativeTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedNegativeTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.apache.sysds.common.Types;
 import org.apache.sysds.runtime.controlprogram.federated.*;
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedRCBindTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedRCBindTest.java
similarity index 97%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedRCBindTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedRCBindTest.java
index 0f28a7b..e59eea8 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedRCBindTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedRCBindTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -79,7 +79,7 @@
 		writeInputMatrixWithMTD("A", A, false, new MatrixCharacteristics(rows, cols, blocksize, rows * cols));
 
 		int port = getRandomAvailablePort();
-		Thread t = startLocalFedWorker(port);
+		Process t = startLocalFedWorker(port);
 
 		// we need the reference file to not be written to hdfs, so we get the correct format
 		rtplatform = Types.ExecMode.SINGLE_NODE;
diff --git a/src/test/java/org/apache/sysds/test/functions/federated/FederatedSumTest.java b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedSumTest.java
similarity index 97%
rename from src/test/java/org/apache/sysds/test/functions/federated/FederatedSumTest.java
rename to src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedSumTest.java
index 69a743c..c6d4be6 100644
--- a/src/test/java/org/apache/sysds/test/functions/federated/FederatedSumTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/federated/primitives/FederatedSumTest.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.sysds.test.functions.federated;
+package org.apache.sysds.test.functions.federated.primitives;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -78,7 +78,7 @@
 		double[][] A = getRandomMatrix(rows / 2, cols, -10, 10, 1, 1);
 		writeInputMatrixWithMTD("A", A, false, new MatrixCharacteristics(rows / 2, cols, blocksize, (rows / 2) * cols));
 		int port = getRandomAvailablePort();
-		Thread t = startLocalFedWorker(port);
+		Process t = startLocalFedWorker(port);
 
 		// we need the reference file to not be written to hdfs, so we get the correct format
 		rtplatform = Types.ExecMode.SINGLE_NODE;
diff --git a/src/test/java/org/apache/sysds/test/functions/privacy/FederatedL2SVMTest.java b/src/test/java/org/apache/sysds/test/functions/privacy/FederatedL2SVMTest.java
index 6ecb5ba..b3180cc 100644
--- a/src/test/java/org/apache/sysds/test/functions/privacy/FederatedL2SVMTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/privacy/FederatedL2SVMTest.java
@@ -314,7 +314,7 @@
 		if(rtplatform == Types.ExecMode.SPARK) {
 			DMLScript.USE_LOCAL_SPARK_CONFIG = true;
 		}
-		Thread t1 = null, t2 = null;
+		Process t1 = null, t2 = null;
 
 		try {
 			getAndLoadTestConfiguration(TEST_NAME);
diff --git a/src/test/java/org/apache/sysds/test/functions/privacy/FederatedWorkerHandlerTest.java b/src/test/java/org/apache/sysds/test/functions/privacy/FederatedWorkerHandlerTest.java
index 3c2cbd6..6c7ce4b 100644
--- a/src/test/java/org/apache/sysds/test/functions/privacy/FederatedWorkerHandlerTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/privacy/FederatedWorkerHandlerTest.java
@@ -154,7 +154,6 @@
 		boolean sparkConfigOld = DMLScript.USE_LOCAL_SPARK_CONFIG;
 		Types.ExecMode platformOld = rtplatform;
 
-		Thread t;
 
 		getAndLoadTestConfiguration("aggregation");
 		String HOME = SCRIPT_DIR + TEST_DIR;
@@ -162,7 +161,7 @@
 		double[][] A = getRandomMatrix(rows, cols, -10, 10, 1, 1);
 		writeInputMatrixWithMTD("A", A, false, new MatrixCharacteristics(rows, cols, blocksize, rows * cols), new PrivacyConstraint(privacyLevel));
 		int port = getRandomAvailablePort();
-		t = startLocalFedWorker(port);
+		Process t = startLocalFedWorker(port);
 
 		// we need the reference file to not be written to hdfs, so we get the correct format
 		rtplatform = Types.ExecMode.SINGLE_NODE;
@@ -224,7 +223,6 @@
 		boolean sparkConfigOld = DMLScript.USE_LOCAL_SPARK_CONFIG;
 		Types.ExecMode platformOld = rtplatform;
 
-		Thread t;
 
 		getAndLoadTestConfiguration("transfer");
 		String HOME = SCRIPT_DIR + TEST_DIR;
@@ -233,7 +231,7 @@
 		writeInputMatrixWithMTD("A", A, false, new MatrixCharacteristics(rows, cols, blocksize, rows * cols), new PrivacyConstraint(privacyLevel));
 
 		int port = getRandomAvailablePort();
-		t = startLocalFedWorker(port);
+		Process t = startLocalFedWorker(port);
 
 		// we need the reference file to not be written to hdfs, so we get the correct format
 		rtplatform = Types.ExecMode.SINGLE_NODE;
@@ -289,7 +287,7 @@
 			DMLScript.USE_LOCAL_SPARK_CONFIG = true;
 		}
 
-		Thread t1, t2;
+		Process t1, t2;
 
 		getAndLoadTestConfiguration("matvecmult");
 		String HOME = SCRIPT_DIR + TEST_DIR;
diff --git a/src/test/java/org/apache/sysds/test/functions/transform/TransformFederatedEncodeDecodeTest.java b/src/test/java/org/apache/sysds/test/functions/transform/TransformFederatedEncodeDecodeTest.java
index 1f9c87d..6a5653e 100644
--- a/src/test/java/org/apache/sysds/test/functions/transform/TransformFederatedEncodeDecodeTest.java
+++ b/src/test/java/org/apache/sysds/test/functions/transform/TransformFederatedEncodeDecodeTest.java
@@ -87,7 +87,7 @@
 		ExecMode platformOld = rtplatform;
 		rtplatform = ExecMode.SINGLE_NODE;
 
-		Thread t1 = null, t2 = null, t3 = null, t4 = null;
+		Process t1 = null, t2 = null, t3 = null, t4 = null;
 		try {
 			getAndLoadTestConfiguration(TEST_NAME1);