Support pausing TestShard writes through ICB (#15299)

Author: alexvru

ydb/core/protos/config.proto

@@ -1573,6 +1573,15 @@ message TImmediateControlsConfig {
             DefaultValue: 0 }];
     }
 
+    message TTestShardControls {
+        optional uint64 DisableWrites = 1 [(ControlOptions) = {
+            Description: "Disable write load in all node TestShard tablets",
+            MinValue: 0,
+            MaxValue: 1,
+            DefaultValue: 0
+        }];
+    }
+
     optional TDataShardControls DataShardControls = 1;
     optional TTxLimitControls TxLimitControls = 2;
     optional TCoordinatorControls CoordinatorControls = 3;
@@ -1585,6 +1594,7 @@ message TImmediateControlsConfig {
     optional TPDiskControls PDiskControls = 10;
     optional TBlobStorageControllerControls BlobStorageControllerControls = 11;
     optional TTableServiceControls TableServiceControls = 12;
+    optional TTestShardControls TestShardControls = 13;
 };
 
 message TMeteringConfig {

ydb/core/test_tablet/load_actor_impl.cpp

@@ -24,6 +24,9 @@ namespace NKikimr::NTestShard {
         } else {
             sys->Send(ev.release());
         }
+
+        auto *appData = AppData();
+        appData->Icb->RegisterSharedControl(DisableWrites, "TestShardControls.DisableWrites");
     }
 
     void TLoadActor::ClearKeys() {
@@ -89,7 +92,7 @@ namespace NKikimr::NTestShard {
             const TMonotonic now = TActivationContext::Monotonic();
 
             bool canWriteMore = false;
-            if (WritesInFlight.size() + PatchesInFlight.size() < Settings.GetMaxInFlight()) {
+            if (WritesInFlight.size() + PatchesInFlight.size() < Settings.GetMaxInFlight() && !DisableWrites) {
                 if (NextWriteTimestamp <= now) {
                     if (Settings.HasPatchRequestsFractionPPM() && !ConfirmedKeys.empty() &&
                             RandomNumber(1'000'000u) < Settings.GetPatchRequestsFractionPPM()) {
@@ -123,6 +126,12 @@ namespace NKikimr::NTestShard {
                 TActivationContext::Send(new IEventHandle(EvDoSomeAction, 0, SelfId(), {}, nullptr, 0));
                 DoSomeActionInFlight = true;
             }
+
+            if (!DoSomeActionInFlight && ReadsInFlight.empty() && WritesInFlight.empty() && PatchesInFlight.empty() &&
+                    DeletesInFlight.empty() && TransitionInFlight.empty()) {
+                TActivationContext::Schedule(TDuration::Seconds(1), new IEventHandle(EvDoSomeAction, 0, SelfId(), {}, nullptr, 0));
+                DoSomeActionInFlight = true;
+            }
         }
     }
 

ydb/core/test_tablet/load_actor_impl.h

@@ -138,6 +138,8 @@ namespace NKikimr::NTestShard {
         bool WriteOnTimeScheduled = false;
         bool DoSomeActionInFlight = false;
 
+        TControlWrapper DisableWrites;
+
         void GenerateKeyValue(TString *key, TString *value, bool *isInline);
         void IssueWrite();
         void IssuePatch();