From 637e7a79d62cc7880b719f02db3316c21eb3a5da Mon Sep 17 00:00:00 2001
From: nandinibhartiyaMDB <nandini.bhartiya@mongodb.com>
Date: Tue, 2 May 2023 22:26:28 +0000
Subject: [PATCH] SERVER-123: Fix delete ops of oplog application

---
 .../sharding/libs/resharding_test_fixture.js  |  9 ++++
 ..._multi_deletes_reduced_ticket_pool_size.js | 48 +++++++++++++++++++
 .../s/resharding/resharding_oplog_applier.cpp |  1 -
 .../resharding_server_parameters.idl          |  2 +-
 4 files changed, 58 insertions(+), 2 deletions(-)
 create mode 100644 jstests/sharding/resharding_with_multi_deletes_reduced_ticket_pool_size.js

diff --git a/jstests/sharding/libs/resharding_test_fixture.js b/jstests/sharding/libs/resharding_test_fixture.js
index e05e82fa1eb..2fdb845d0b5 100644
--- a/jstests/sharding/libs/resharding_test_fixture.js
+++ b/jstests/sharding/libs/resharding_test_fixture.js
@@ -35,6 +35,7 @@ var ReshardingTest = class {
         logComponentVerbosity: logComponentVerbosity = undefined,
         storeFindAndModifyImagesInSideCollection: storeFindAndModifyImagesInSideCollection = true,
         oplogSize: oplogSize = undefined,
+        wiredTigerConcurrentWriteTransactions: wiredTigerConcurrentWriteTransactions = undefined,
         maxNumberOfTransactionOperationsInSingleOplogEntry:
             maxNumberOfTransactionOperationsInSingleOplogEntry = undefined,
         configShard: configShard = false,
@@ -67,6 +68,7 @@ var ReshardingTest = class {
         /** @private */
         this._storeFindAndModifyImagesInSideCollection = storeFindAndModifyImagesInSideCollection;
         this._oplogSize = oplogSize;
+        this._wiredTigerConcurrentWriteTransactions = wiredTigerConcurrentWriteTransactions;
         this._maxNumberOfTransactionOperationsInSingleOplogEntry =
             maxNumberOfTransactionOperationsInSingleOplogEntry;
         this._configShard = configShard || jsTestOptions().configShard;
@@ -172,6 +174,13 @@ var ReshardingTest = class {
             mongosOptions.setParameter.logComponentVerbosity = this._logComponentVerbosity;
         }
 
+        if (this._wiredTigerConcurrentWriteTransactions !== undefined) {
+            rsOptions.setParameter.storageEngineConcurrencyAdjustmentAlgorithm =
+                "fixedConcurrentTransactions";
+            rsOptions.setParameter.wiredTigerConcurrentWriteTransactions =
+                this._wiredTigerConcurrentWriteTransactions;
+        }
+
         if (this._maxNumberOfTransactionOperationsInSingleOplogEntry !== undefined) {
             rsOptions.setParameter.maxNumberOfTransactionOperationsInSingleOplogEntry =
                 this._maxNumberOfTransactionOperationsInSingleOplogEntry;
diff --git a/jstests/sharding/resharding_with_multi_deletes_reduced_ticket_pool_size.js b/jstests/sharding/resharding_with_multi_deletes_reduced_ticket_pool_size.js
new file mode 100644
index 00000000000..f1ec4af65fd
--- /dev/null
+++ b/jstests/sharding/resharding_with_multi_deletes_reduced_ticket_pool_size.js
@@ -0,0 +1,48 @@
+/**
+ * Test the correctness of multi deletes during resharding.
+ *
+ * @tags: [
+ *  requires_sharding,
+ * ]
+ */
+
+(function() {
+"use strict";
+
+load("jstests/libs/discover_topology.js");
+load("jstests/sharding/libs/resharding_test_fixture.js");
+
+const kNumWriteTickets = 5;
+const reshardingTest =
+    new ReshardingTest({wiredTigerConcurrentWriteTransactions: kNumWriteTickets});
+
+reshardingTest.setup();
+
+const donorShardNames = reshardingTest.donorShardNames;
+const sourceCollection = reshardingTest.createShardedCollection({
+    ns: "reshardingDb.coll",
+    shardKeyPattern: {oldKey: 1},
+    chunks: [{min: {oldKey: MinKey}, max: {oldKey: MaxKey}, shard: donorShardNames[0]}],
+});
+for (let i = 0; i < 10; i++) {
+    assert.commandWorked(sourceCollection.insert([{x: 1}]));
+}
+assert.commandWorked(sourceCollection.insert([{x: 3}, {x: 3}]));
+const mongos = sourceCollection.getMongo();
+const topology = DiscoverTopology.findConnectedNodes(mongos);
+const coordinator = new Mongo(topology.configsvr.nodes[0]);
+const recipientShardNames = reshardingTest.recipientShardNames;
+reshardingTest.withReshardingInBackground(
+    {
+        newShardKeyPattern: {newKey: 1},
+        newChunks: [{min: {newKey: MinKey}, max: {newKey: MaxKey}, shard: recipientShardNames[0]}],
+    },
+    () => {
+        // We wait until cloneTimestamp has been chosen to guarantee that any subsequent writes will
+        // be applied by the ReshardingOplogApplier.
+        reshardingTest.awaitCloneTimestampChosen();
+
+        assert.commandWorked(sourceCollection.remove({x: 1}, {justOne: false}));
+    });
+reshardingTest.teardown();
+})();
diff --git a/src/mongo/db/s/resharding/resharding_oplog_applier.cpp b/src/mongo/db/s/resharding/resharding_oplog_applier.cpp
index 51632cb40cc..4f4d1f1b035 100644
--- a/src/mongo/db/s/resharding/resharding_oplog_applier.cpp
+++ b/src/mongo/db/s/resharding/resharding_oplog_applier.cpp
@@ -90,7 +90,6 @@ SemiFuture<void> ReshardingOplogApplier::_applyBatch(
     // though allows CRUD application to be concurrent with preparing the writer vectors for session
     // application in addition to being concurrent with session application itself.
     batchApplierFutures.reserve(2 * crudWriterVectors.size());
-
     for (auto&& writer : crudWriterVectors) {
         if (!writer.empty()) {
             batchApplierFutures.emplace_back(
diff --git a/src/mongo/db/s/resharding/resharding_server_parameters.idl b/src/mongo/db/s/resharding/resharding_server_parameters.idl
index ea5703cf34d..644df507a06 100644
--- a/src/mongo/db/s/resharding/resharding_server_parameters.idl
+++ b/src/mongo/db/s/resharding/resharding_server_parameters.idl
@@ -60,7 +60,7 @@ server_parameters:
         set_at: startup
         cpp_vartype: int
         cpp_varname: gReshardingRecipientServiceMaxThreadCount
-        default: 8
+        default: 20
         validator:
             gte: 1
             lte: 256
-- 
2.17.1