SERVER-38436 Add concurrency workload for majority writes alongside transactions

1 files changed, 105 insertions, 0 deletions

diff --git a/jstests/concurrency/fsm_workloads/multi_statement_transaction_simple_majority_writes.js b/jstests/concurrency/fsm_workloads/multi_statement_transaction_simple_majority_writes.js
new file mode 100644
index 00000000000..2e52765014c
--- /dev/null
+++ b/jstests/concurrency/fsm_workloads/multi_statement_transaction_simple_majority_writes.js
@@ -0,0 +1,105 @@
+'use strict';
+
+/**
+ * Performs concurrent majority writes alongside transactions to verify both will eventually
+ * complete as expected.
+ *
+ * The base workload assumes transactions run at snapshot read concern, so the tag is copied here.
+ * @tags: [uses_transactions, assumes_snapshot_transactions]
+ */
+
+load('jstests/concurrency/fsm_libs/extend_workload.js');  // for extendWorkload
+load('jstests/concurrency/fsm_workloads/multi_statement_transaction_simple.js');  // for $config
+load('jstests/concurrency/fsm_workload_helpers/server_types.js');                 // for isMongos
+
+var $config = extendWorkload($config, function($config, $super) {
+
+    $config.data.majorityWriteCollName = 'majority_writes';
+    $config.data.counter = 0;
+
+    /**
+     * Runs the base workload's init state function and inserts a document to be majority updated
+     * later by this thread.
+     */
+    $config.states.init = function init(db, collName) {
+        $super.states.init.apply(this, arguments);
+
+        assertWhenOwnColl.writeOK(db[this.majorityWriteCollName].insert(
+            {_id: this.tid, counter: this.counter}, {writeConcern: {w: 'majority'}}));
+    };
+
+    /**
+     * Updates a document unrelated to the transaction run in the base workload using majority write
+     * concern and verifies the update is immediately visible in the majority snapshot once the
+     * write returns.
+     */
+    $config.states.majorityWriteUnrelatedDoc = function majorityWriteUnrelatedDoc(db, collName) {
+        this.counter += 1;
+        assertWhenOwnColl.writeOK(db[this.majorityWriteCollName].update(
+            {_id: this.tid}, {$set: {counter: this.counter}}, {writeConcern: {w: 'majority'}}));
+
+        // As soon as the write returns, its effects should be visible in the majority snapshot.
+        const doc = db[this.majorityWriteCollName].findOne({_id: this.tid});
+        assertWhenOwnColl.eq(
+            this.counter, doc.counter, 'unexpected counter value, doc: ' + tojson(doc));
+    };
+
+    /**
+     * Updates a document that may be written to by the transaction run in the base workload using
+     * majority write concern and verifies the update is immediately visible in the majority
+     * snapshot once the write returns.
+     */
+    $config.states.majorityWriteTxnDoc = function majorityWriteTxnDoc(db, collName) {
+        this.counter += 1;
+
+        // Choose a random document that may be written to by the base workload. The base collection
+        // contains documents with _id ranging from 0 to the number of accounts. Update a field
+        // based on the thread's id, since threads may concurrently write to the same document.
+        const transactionDocId = Random.randInt(this.numAccounts);
+        const threadUniqueField = 'thread' + this.tid;
+        assertWhenOwnColl.writeOK(db[collName].update({_id: transactionDocId},
+                                                      {$set: {[threadUniqueField]: this.counter}},
+                                                      {writeConcern: {w: 'majority'}}));
+
+        // As soon as the write returns, its effects should be visible in the majority snapshot.
+        const doc = db[collName].findOne({_id: transactionDocId});
+        assertWhenOwnColl.eq(
+            this.counter,
+            doc[threadUniqueField],
+            'unexpected thread unique field value, thread: ' + this.tid + ', doc: ' + tojson(doc));
+    };
+
+    /**
+     * Runs the base workload's setup and, if necessary, shards the collection that is majority
+     * written to by this workload.
+     */
+    $config.setup = function setup(db, collName, cluster) {
+        $super.setup.apply(this, arguments);
+
+        if (isMongos(db)) {
+            // The database will already have had sharding enabled by the fsm infrastructure.
+            db.adminCommand({
+                shardCollection: db[this.majorityWriteCollName].getFullName(),
+                key: {_id: 'hashed'}
+            });
+        }
+    };
+
+    $config.transitions = {
+        init: {transferMoney: 1},
+        transferMoney: {
+            transferMoney: 0.5,
+            checkMoneyBalance: 0.1,
+            majorityWriteUnrelatedDoc: 0.2,
+            majorityWriteTxnDoc: 0.2
+        },
+        checkMoneyBalance:
+            {transferMoney: 0.5, majorityWriteUnrelatedDoc: 0.25, majorityWriteTxnDoc: 0.25},
+        majorityWriteUnrelatedDoc:
+            {transferMoney: 0.5, majorityWriteUnrelatedDoc: 0.25, majorityWriteTxnDoc: 0.25},
+        majorityWriteTxnDoc:
+            {transferMoney: 0.5, majorityWriteUnrelatedDoc: 0.25, majorityWriteTxnDoc: 0.25},
+    };
+
+    return $config;
+});