diff --git a/ydb/core/tablet/resource_broker.cpp b/ydb/core/tablet/resource_broker.cpp
index 05f4f79b772d..29cb3dc06072 100644
--- a/ydb/core/tablet/resource_broker.cpp
+++ b/ydb/core/tablet/resource_broker.cpp
@@ -1302,7 +1302,7 @@ NKikimrResourceBroker::TResourceBrokerConfig MakeDefaultConfig()
 
     const ui64 DefaultQueueCPU = 2;
     const ui64 KqpRmQueueCPU = 4;
-    const ui64 TotalCPU = 20;
+    const ui64 TotalCPU = 256; // means unlimited
 
     // Note: these memory limits will be overwritten by MemoryController
     const ui64 KqpRmQueueMemory = 10_GB;
diff --git a/ydb/core/tablet/resource_broker_ut.cpp b/ydb/core/tablet/resource_broker_ut.cpp
index aa2ba8131c08..7c3157e5b973 100644
--- a/ydb/core/tablet/resource_broker_ut.cpp
+++ b/ydb/core/tablet/resource_broker_ut.cpp
@@ -15,13 +15,13 @@ namespace NKikimr {
 using namespace NKikimrResourceBroker;
 using namespace NResourceBroker;
 
-static void SetupLogging(TTestActorRuntime& runtime) {
+static void SetupLogging(TTestActorRuntime& runtime)
+{
     NActors::NLog::EPriority priority = ENABLE_DETAILED_RESOURCE_BROKER_LOG ? NLog::PRI_DEBUG : NLog::PRI_ERROR;
     runtime.SetLogPriority(NKikimrServices::RESOURCE_BROKER, priority);
 }
 
-static NKikimrResourceBroker::TResourceBrokerConfig
-MakeTestConfig()
+static NKikimrResourceBroker::TResourceBrokerConfig MakeTestConfig()
 {
     NKikimrResourceBroker::TResourceBrokerConfig config;
 
@@ -71,16 +71,14 @@ MakeTestConfig()
     return config;
 }
 
-static void
-WaitForBootstrap(TTestActorRuntime &runtime)
+static void WaitForBootstrap(TTestActorRuntime &runtime)
 {
     TDispatchOptions options;
     options.FinalEvents.emplace_back(TEvents::TSystem::Bootstrap, 1);
     UNIT_ASSERT(runtime.DispatchEvents(options));
 }
 
-static void
-SubmitTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
+static void SubmitTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
            ui64 id, ui64 cpu, ui64 memory, const TString &type,
            ui32 priority, TIntrusivePtr<TThrRefBase> cookie = nullptr)
 {
@@ -94,8 +92,7 @@ SubmitTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
     runtime.Send(new IEventHandle(broker, sender, event.Release()));
 }
 
-static void
-UpdateTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
+static void UpdateTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
            ui64 id, ui64 cpu, ui64 memory, ui32 priority, const TString &type,
            bool resubmit = false)
 {
@@ -107,8 +104,7 @@ UpdateTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
     runtime.Send(new IEventHandle(broker, sender, event.Release()));
 }
 
-static void
-UpdateTaskCookie(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
+static void UpdateTaskCookie(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
                  ui64 id, TIntrusivePtr<TThrRefBase> cookie)
 {
     TAutoPtr<TEvResourceBroker::TEvUpdateTaskCookie> event
@@ -117,8 +113,7 @@ UpdateTaskCookie(TTestActorRuntime &runtime, TActorId broker, TActorId sender,
     runtime.Send(new IEventHandle(broker, sender, event.Release()));
 }
 
-static void
-RemoveTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender, ui64 id)
+static void RemoveTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender, ui64 id)
 {
     TAutoPtr<TEvResourceBroker::TEvRemoveTask> event
         = new TEvResourceBroker::TEvRemoveTask(id);
@@ -126,8 +121,7 @@ RemoveTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender, ui64 id
     runtime.Send(new IEventHandle(broker, sender, event.Release()));
 }
 
-static void
-FinishTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender, ui64 id)
+static void FinishTask(TTestActorRuntime &runtime, TActorId broker, TActorId sender, ui64 id)
 {
     TAutoPtr<TEvResourceBroker::TEvFinishTask> event
         = new TEvResourceBroker::TEvFinishTask(id);
@@ -147,8 +141,7 @@ WaitForResourceAllocation(TTestActorRuntime &runtime, ui64 id,
     return reply->TaskId;
 }
 
-static void
-WaitForError(TTestActorRuntime &runtime, ui64 id, TEvResourceBroker::TStatus::ECode code,
+static void WaitForError(TTestActorRuntime &runtime, ui64 id, TEvResourceBroker::TStatus::ECode code,
              TIntrusivePtr<TThrRefBase> cookie = nullptr)
 {
     TAutoPtr<IEventHandle> handle;
@@ -158,8 +151,7 @@ WaitForError(TTestActorRuntime &runtime, ui64 id, TEvResourceBroker::TStatus::EC
     UNIT_ASSERT_VALUES_EQUAL(reply->Cookie, cookie);
 }
 
-static void
-CheckCounters(::NMonitoring::TDynamicCounterPtr counters, const TString &group, const TString &name,
+static void CheckCounters(::NMonitoring::TDynamicCounterPtr counters, const TString &group, const TString &name,
               ui64 cpu, ui64 memory, ui64 finished, ui64 enqueued, ui64 infly)
 {
     auto g = counters->GetSubgroup(group, name);
@@ -185,14 +177,14 @@ static void CheckConfigure(TTestActorRuntime &runtime, TActorId broker, TActorId
     UNIT_ASSERT_VALUES_EQUAL((int)rec.GetSuccess(), (int)success);
 }
 
-static
-TIntrusivePtr<IResourceBroker> GetInstantResourceBroker(TTestActorRuntime &runtime, TActorId broker, TActorId sender) {
+static TIntrusivePtr<IResourceBroker> GetInstantResourceBroker(TTestActorRuntime &runtime, TActorId broker, TActorId sender) {
     runtime.Send(new IEventHandle(broker, sender, new TEvResourceBroker::TEvResourceBrokerRequest));
     auto answer = runtime.GrabEdgeEvent<TEvResourceBroker::TEvResourceBrokerResponse>(sender);
     return answer->Get()->ResourceBroker;
 }
 
 Y_UNIT_TEST_SUITE(TResourceBroker) {
+
     Y_UNIT_TEST(TestErrors) {
         TTestBasicRuntime runtime;
         SetupTabletServices(runtime);
@@ -894,6 +886,7 @@ Y_UNIT_TEST_SUITE(TResourceBroker) {
 };
 
 Y_UNIT_TEST_SUITE(TResourceBrokerInstant) {
+
     Y_UNIT_TEST(Test) {
         TTestBasicRuntime runtime;
         SetupTabletServices(runtime);
@@ -1007,6 +1000,7 @@ Y_UNIT_TEST_SUITE(TResourceBrokerInstant) {
             CheckCounters(counters, "queue", "total", 210, 320, 1, 0, 2);
         }
     }
+
 };
 
 Y_UNIT_TEST_SUITE(TResourceBrokerConfig) {
@@ -1130,6 +1124,21 @@ Y_UNIT_TEST_SUITE(TResourceBrokerConfig) {
         UNIT_ASSERT_VALUES_EQUAL(config.ShortDebugString(), "ResourceLimit { Cpu: 20 Memory: 2048 }");
     }
 
+    Y_UNIT_TEST(DefaultConfig) {
+        auto config = MakeDefaultConfig();
+
+        Cerr << config.DebugString() << Endl;
+
+        ui64 queuesCpu = 0;
+        for (const auto& q : config.GetQueues()) {
+            queuesCpu += q.GetLimit().GetCpu();
+        }
+        Cerr << "Total queues cpu: " << queuesCpu;
+
+        // see https://github.com/ydb-platform/ydb/issues/18513
+        UNIT_ASSERT_LE(queuesCpu, config.GetResourceLimit().GetCpu());
+    }
+
 } // TResourceBrokerConfig
 
 } // NKikimr