From cf3a5e9ef12b96eab59be07383deb0ef9d818ab3 Mon Sep 17 00:00:00 2001
From: Marcos Grillo <marcos.grillo@mongodb.com>
Date: Mon, 27 Oct 2025 17:00:49 +0100
Subject: [PATCH] SERVER-112570 Fix priority stats with the new ticketing
 system implementation (#42926)

GitOrigin-RevId: d3b89976277f0099ac5b41f6b30cfbb799ac8fa0
---
 ...ion_control_stats_change_with_algorithm.js | 76 +++++++++++++++++++
 src/mongo/db/admission/ticketing_system.cpp   | 15 +++-
 2 files changed, 87 insertions(+), 4 deletions(-)
 create mode 100644 jstests/noPassthrough/admission/execution_control_stats_change_with_algorithm.js

diff --git a/jstests/noPassthrough/admission/execution_control_stats_change_with_algorithm.js b/jstests/noPassthrough/admission/execution_control_stats_change_with_algorithm.js
new file mode 100644
index 00000000000..338d2bcc350
--- /dev/null
+++ b/jstests/noPassthrough/admission/execution_control_stats_change_with_algorithm.js
@@ -0,0 +1,76 @@
+/**
+ * Checks the statistic scheme of the different execution control algorithms.
+ *
+ * @tags: [
+ *      featureFlagMultipleTicketPoolsExecutionControl,
+ * ]
+ */
+
+import {ReplSetTest} from "jstests/libs/replsettest.js";
+
+function assertTicketStatsScheme(bool, obj) {
+    assert.eq(bool, obj.hasOwnProperty("out"));
+    assert.eq(bool, obj.hasOwnProperty("available"));
+    assert.eq(bool, obj.hasOwnProperty("totalTickets"));
+}
+
+function assertNormalScheme(obj) {
+    assertTicketStatsScheme(true, obj);
+    assert.eq(true, obj.hasOwnProperty("exempt"));
+    assertTicketStatsScheme(false, obj.exempt);
+    assert.eq(false, obj.hasOwnProperty("lowPriority"));
+    assert.eq(true, obj.hasOwnProperty("normalPriority"));
+    assertTicketStatsScheme(false, obj.normalPriority);
+}
+
+function assertDeprioritizationScheme(obj) {
+    assertTicketStatsScheme(true, obj);
+    assert.eq(true, obj.hasOwnProperty("lowPriority"));
+    assertTicketStatsScheme(true, obj.lowPriority);
+    assert.eq(true, obj.hasOwnProperty("normalPriority"));
+    assertTicketStatsScheme(true, obj.normalPriority);
+    assert.eq(true, obj.hasOwnProperty("exempt"));
+    assertTicketStatsScheme(false, obj.exempt);
+}
+
+const rst = new ReplSetTest({
+    nodes: 1,
+});
+
+rst.startSet();
+rst.initiate();
+
+const primary = rst.getPrimary();
+const db = primary.getDB(jsTestName());
+
+assert.commandWorked(
+    rst.getPrimary().adminCommand({
+        setParameter: 1,
+        storageEngineConcurrencyAdjustmentAlgorithm: "throughputProbing",
+    }),
+);
+
+const serverStatus = db.serverStatus().queues.execution.read;
+assertNormalScheme(serverStatus);
+
+assert.commandWorked(
+    rst.getPrimary().adminCommand({
+        setParameter: 1,
+        storageEngineConcurrencyAdjustmentAlgorithm: "fixedConcurrentTransactions",
+    }),
+);
+
+const serverStatusFixedTxns = db.serverStatus().queues.execution.read;
+assertNormalScheme(serverStatusFixedTxns);
+
+assert.commandWorked(
+    rst.getPrimary().adminCommand({
+        setParameter: 1,
+        storageEngineConcurrencyAdjustmentAlgorithm: "fixedConcurrentTransactionsWithPrioritization",
+    }),
+);
+
+const serverStatusFixedTxnsPrioritization = db.serverStatus().queues.execution.read;
+assertDeprioritizationScheme(serverStatusFixedTxnsPrioritization);
+
+rst.stopSet();
diff --git a/src/mongo/db/admission/ticketing_system.cpp b/src/mongo/db/admission/ticketing_system.cpp
index fb7835096a1..ec6ef8480f9 100644
--- a/src/mongo/db/admission/ticketing_system.cpp
+++ b/src/mongo/db/admission/ticketing_system.cpp
@@ -367,8 +367,11 @@ void TicketingSystem::appendStats(BSONObjBuilder& b) const {
     for (size_t i = 0; i < _holders.size(); ++i) {
         const auto priority = static_cast<AdmissionContext::Priority>(i);
 
-        if (priority == AdmissionContext::Priority::kExempt) {
-            // Do not report statistics for kExempt as they are included in the normal priority pool
+        if (priority == AdmissionContext::Priority::kExempt ||
+            (priority == AdmissionContext::Priority::kLow && !usesPrioritization())) {
+            // Do not report statistics for kExempt as they are included in the normal priority
+            // pool. Also, low priority statistics should only be reported when prioritization is
+            // enabled.
             continue;
         }
 
@@ -385,7 +388,9 @@ void TicketingSystem::appendStats(BSONObjBuilder& b) const {
                 readStats.emplace();
             }
             BSONObjBuilder bb(readStats->subobjStart(fieldName));
-            rw.read->appendTicketStats(bb);
+            if (usesPrioritization()) {
+                rw.read->appendTicketStats(bb);
+            }
             rw.read->appendHolderStats(bb);
             bb.done();
             if (priority == AdmissionContext::Priority::kNormal) {
@@ -402,7 +407,9 @@ void TicketingSystem::appendStats(BSONObjBuilder& b) const {
                 writeStats.emplace();
             }
             BSONObjBuilder bb(writeStats->subobjStart(fieldName));
-            rw.write->appendTicketStats(bb);
+            if (usesPrioritization()) {
+                rw.write->appendTicketStats(bb);
+            }
             rw.write->appendHolderStats(bb);
             bb.done();
             if (priority == AdmissionContext::Priority::kNormal) {