SERVER-50703 Create global resource consumption structure

4 files changed, 243 insertions, 0 deletions

diff --git a/src/mongo/db/stats/SConscript b/src/mongo/db/stats/SConscript
index 15138462b01..d805e0cc6ea 100644
--- a/src/mongo/db/stats/SConscript
+++ b/src/mongo/db/stats/SConscript
@@ -75,6 +75,7 @@ env.Library(
 env.Library(
     target='resource_consumption_metrics',
     source=[
+        'resource_consumption_metrics.cpp',
         env.Idlc('operation_resource_consumption.idl')[0],
     ],
     LIBDEPS=[
@@ -133,6 +134,7 @@ env.CppUnitTest(
         'api_version_metrics_test.cpp',
         'fill_locker_info_test.cpp',
         'operation_latency_histogram_test.cpp',
+        'resource_consumption_metrics_test.cpp',
         'timer_stats_test.cpp',
         'top_test.cpp',
     ],
@@ -143,6 +145,7 @@ env.CppUnitTest(
         '$BUILD_DIR/mongo/util/clock_source_mock',
         'api_version_metrics',
         'fill_locker_info',
+        'resource_consumption_metrics',
         'timer_stats',
         'top',
     ],
diff --git a/src/mongo/db/stats/resource_consumption_metrics.cpp b/src/mongo/db/stats/resource_consumption_metrics.cpp
new file mode 100644
index 00000000000..a5bb969042a
--- /dev/null
+++ b/src/mongo/db/stats/resource_consumption_metrics.cpp
@@ -0,0 +1,64 @@
+/**
+ *    Copyright (C) 2020-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/db/stats/resource_consumption_metrics.h"
+
+namespace mongo {
+namespace {
+const OperationContext::Decoration<ResourceConsumption::Metrics> getOperationMetrics =
+    OperationContext::declareDecoration<ResourceConsumption::Metrics>();
+const ServiceContext::Decoration<ResourceConsumption> getGlobalResourceConsumption =
+    ServiceContext::declareDecoration<ResourceConsumption>();
+}  // namespace
+
+
+ResourceConsumption::Metrics& ResourceConsumption::Metrics::get(OperationContext* opCtx) {
+    return getOperationMetrics(opCtx);
+}
+
+ResourceConsumption& ResourceConsumption::get(ServiceContext* svcCtx) {
+    return getGlobalResourceConsumption(svcCtx);
+}
+
+ResourceConsumption& ResourceConsumption::get(OperationContext* opCtx) {
+    return getGlobalResourceConsumption(opCtx->getServiceContext());
+}
+
+void ResourceConsumption::add(const Metrics& metrics) {
+    invariant(!metrics.getDbName().empty());
+    stdx::unique_lock<Mutex> lk(_mutex);
+    _metrics[metrics.getDbName()] += metrics;
+}
+
+ResourceConsumption::MetricsMap ResourceConsumption::getMetrics() const {
+    stdx::unique_lock<Mutex> lk(_mutex);
+    return _metrics;
+}
+
+}  // namespace mongo
diff --git a/src/mongo/db/stats/resource_consumption_metrics.h b/src/mongo/db/stats/resource_consumption_metrics.h
new file mode 100644
index 00000000000..257039ca17f
--- /dev/null
+++ b/src/mongo/db/stats/resource_consumption_metrics.h
@@ -0,0 +1,100 @@
+/**
+ *    Copyright (C) 2020-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <map>
+#include <string>
+
+#include "mongo/db/operation_context.h"
+#include "mongo/platform/mutex.h"
+
+namespace mongo {
+
+/**
+ * ResourceConsumption maintains thread-safe access into a map of resource consumption Metrics.
+ */
+class ResourceConsumption {
+public:
+    static ResourceConsumption& get(OperationContext* opCtx);
+    static ResourceConsumption& get(ServiceContext* svcCtx);
+
+    /**
+     * Metrics maintains non-thread-safe, per-operation resource consumption metrics for a specific
+     * database.
+     */
+    class Metrics {
+    public:
+        static Metrics& get(OperationContext* opCtx);
+
+        /**
+         * Adds other Metrics to this one.
+         */
+        void add(const Metrics& other){};
+        Metrics& operator+=(const Metrics& other) {
+            add(other);
+            return *this;
+        }
+
+        /**
+         * Set the database name associated with these metrics.
+         */
+        void setDbName(const std::string& dbName) {
+            _dbName = dbName;
+        }
+
+        const std::string& getDbName() const {
+            return _dbName;
+        }
+
+    private:
+        std::string _dbName;
+    };
+
+    /**
+     * Adds a Metrics object to an existing Metrics object in the map, keyed by database name. If no
+     * Metrics exist for the database, the value is initialized with the provided Metrics.
+     *
+     * The Metrics database name must not be an empty string.
+     */
+    void add(const Metrics& metrics);
+
+    /**
+     * Returns a copy of the Metrics map.
+     */
+    using MetricsMap = std::map<std::string, Metrics>;
+    MetricsMap getMetrics() const;
+
+private:
+    // Protects _metrics
+    mutable Mutex _mutex = MONGO_MAKE_LATCH("ResourceConsumption::_mutex");
+    MetricsMap _metrics;
+};
+
+}  // namespace mongo
diff --git a/src/mongo/db/stats/resource_consumption_metrics_test.cpp b/src/mongo/db/stats/resource_consumption_metrics_test.cpp
new file mode 100644
index 00000000000..093170ec199
--- /dev/null
+++ b/src/mongo/db/stats/resource_consumption_metrics_test.cpp
@@ -0,0 +1,76 @@
+/**
+ *    Copyright (C) 2020-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/service_context_test_fixture.h"
+#include "mongo/db/stats/resource_consumption_metrics.h"
+#include "mongo/unittest/unittest.h"
+
+namespace mongo {
+
+class ResourceConsumptionMetricsTest : public ServiceContextTest {
+public:
+    void setUp() {
+        _opCtx = makeOperationContext();
+    }
+
+    typedef std::pair<ServiceContext::UniqueClient, ServiceContext::UniqueOperationContext>
+        ClientAndCtx;
+    ClientAndCtx makeClientAndCtx(const std::string& clientName) {
+        auto client = getServiceContext()->makeClient(clientName);
+        auto opCtx = client->makeOperationContext();
+        return std::make_pair(std::move(client), std::move(opCtx));
+    }
+
+protected:
+    ServiceContext::UniqueOperationContext _opCtx;
+};
+
+TEST_F(ResourceConsumptionMetricsTest, Add) {
+    auto& globalResourceConsumption = ResourceConsumption::get(getServiceContext());
+
+    auto [client2, opCtx2] = makeClientAndCtx("opCtx2");
+
+    auto& operationMetrics1 = ResourceConsumption::Metrics::get(_opCtx.get());
+    auto& operationMetrics2 = ResourceConsumption::Metrics::get(opCtx2.get());
+
+    operationMetrics1.setDbName("db1");
+    operationMetrics2.setDbName("db2");
+    globalResourceConsumption.add(operationMetrics1);
+    globalResourceConsumption.add(operationMetrics1);
+    globalResourceConsumption.add(operationMetrics2);
+    globalResourceConsumption.add(operationMetrics2);
+
+    auto globalMetrics = globalResourceConsumption.getMetrics();
+    ASSERT_EQ(globalMetrics.count("db1"), 1);
+    ASSERT_EQ(globalMetrics.count("db2"), 1);
+    ASSERT_EQ(globalMetrics.count("db3"), 0);
+}
+}  // namespace mongo