diff --git a/assembly/assembly-wsmaster-war/src/main/webapp/WEB-INF/classes/che/che.properties b/assembly/assembly-wsmaster-war/src/main/webapp/WEB-INF/classes/che/che.properties
index a710e27669..09b483301d 100644
--- a/assembly/assembly-wsmaster-war/src/main/webapp/WEB-INF/classes/che/che.properties
+++ b/assembly/assembly-wsmaster-war/src/main/webapp/WEB-INF/classes/che/che.properties
@@ -629,20 +629,20 @@ che.server.secure_exposer.jwtproxy.memory_limit=128mb
 # in case if pool size would be exceeded message execution will be rejected
 che.core.jsonrpc.processor_max_pool_size=50
 # Initial json processing pool. Minimum number of threads that used to process major JSON RPC messages.
-che.core.jsonrpc.processor_core_pool_size=3
+che.core.jsonrpc.processor_core_pool_size=5
 # Configuration of queue used to process Json RPC messages.
 # org.eclipse.che.commons.lang.execution.ExecutorServiceProvider contains more information about this parameter
-che.core.jsonrpc.processor_queue_capacity=10000000
+che.core.jsonrpc.processor_queue_capacity=100000
 
 ## Configuration of major "/websocket-minor" endpoint
 # Maximum size of the JSON RPC processing pool
 # in case if pool size would be exceeded message execution will be rejected
 che.core.jsonrpc.minor_processor_max_pool_size=100
 # Initial json processing pool. Minimum number of threads that used to process minor JSON RPC messages.
-che.core.jsonrpc.minor_processor_core_pool_size=5
+che.core.jsonrpc.minor_processor_core_pool_size=15
 # Configuration of queue used to process Json RPC messages.
 # org.eclipse.che.commons.lang.execution.ExecutorServiceProvider contains more information about this parameter
-che.core.jsonrpc.minor_processor_queue_capacity=100
+che.core.jsonrpc.minor_processor_queue_capacity=10000
 
 ## Port the the http server endpoint that would be exposed with Prometheus metrics
 che.metrics.port=8087
diff --git a/multiuser/permission/che-multiuser-permission-workspace/src/main/java/org/eclipse/che/multiuser/permission/workspace/server/model/impl/WorkerImpl.java b/multiuser/permission/che-multiuser-permission-workspace/src/main/java/org/eclipse/che/multiuser/permission/workspace/server/model/impl/WorkerImpl.java
index f36912e7fb..df509ba980 100644
--- a/multiuser/permission/che-multiuser-permission-workspace/src/main/java/org/eclipse/che/multiuser/permission/workspace/server/model/impl/WorkerImpl.java
+++ b/multiuser/permission/che-multiuser-permission-workspace/src/main/java/org/eclipse/che/multiuser/permission/workspace/server/model/impl/WorkerImpl.java
@@ -22,6 +22,7 @@ import javax.persistence.JoinColumn;
 import javax.persistence.ManyToOne;
 import javax.persistence.NamedQueries;
 import javax.persistence.NamedQuery;
+import javax.persistence.QueryHint;
 import javax.persistence.Table;
 import org.eclipse.che.api.workspace.server.model.impl.WorkspaceImpl;
 import org.eclipse.che.multiuser.api.permission.server.model.impl.AbstractPermissions;
@@ -54,7 +55,8 @@ import org.eclipse.che.multiuser.permission.workspace.server.model.Worker;
           "SELECT worker "
               + "FROM Worker worker "
               + "WHERE worker.userId = :userId "
-              + "AND worker.workspaceId = :workspaceId ")
+              + "AND worker.workspaceId = :workspaceId ",
+      hints = {@QueryHint(name = "eclipselink.query-results-cache", value = "true")})
 })
 @Table(name = "che_worker")
 public class WorkerImpl extends AbstractPermissions implements Worker {
diff --git a/multiuser/permission/che-multiuser-permission-workspace/src/test/java/org/eclipse/che/multiuser/permission/workspace/server/spi/tck/WorkerDaoTest.java b/multiuser/permission/che-multiuser-permission-workspace/src/test/java/org/eclipse/che/multiuser/permission/workspace/server/spi/tck/WorkerDaoTest.java
index d61fd840d5..f50f0c576a 100644
--- a/multiuser/permission/che-multiuser-permission-workspace/src/test/java/org/eclipse/che/multiuser/permission/workspace/server/spi/tck/WorkerDaoTest.java
+++ b/multiuser/permission/che-multiuser-permission-workspace/src/test/java/org/eclipse/che/multiuser/permission/workspace/server/spi/tck/WorkerDaoTest.java
@@ -11,13 +11,13 @@
  */
 package org.eclipse.che.multiuser.permission.workspace.server.spi.tck;
 
-import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertTrue;
+import static org.testng.Assert.*;
 
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
+import java.util.concurrent.Callable;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import javax.inject.Inject;
@@ -199,6 +199,7 @@ public class WorkerDaoTest {
   public void shouldRemoveWorker() throws Exception {
     workerDao.removeWorker("ws1", "user1");
     assertEquals(1, workerDao.getWorkersByUser("user1").size());
+    assertNull(notFoundToNull(() -> workerDao.getWorker("ws1", "user1")));
   }
 
   @Test(expectedExceptions = NullPointerException.class)
@@ -234,4 +235,12 @@ public class WorkerDaoTest {
       return new WorkerImpl(userId, instanceId, allowedActions);
     }
   }
+
+  private static <T> T notFoundToNull(Callable<T> action) throws Exception {
+    try {
+      return action.call();
+    } catch (NotFoundException x) {
+      return null;
+    }
+  }
 }