SERVER-24607 Add Collector for system statistics

4 files changed, 147 insertions, 3 deletions

diff --git a/src/mongo/db/ftdc/SConscript b/src/mongo/db/ftdc/SConscript
index 6c85eda4b80..20294484bb4 100644
--- a/src/mongo/db/ftdc/SConscript
+++ b/src/mongo/db/ftdc/SConscript
@@ -28,10 +28,18 @@ ftdcEnv.Library(
     ],
 )
 
+platform_libs = []
+
+if env.TargetOSIs('linux'):
+    platform_libs = [
+        '$BUILD_DIR/mongo/util/procparser'
+    ]
+
 env.Library(
     target='ftdc_mongod',
     source=[
         'ftdc_mongod.cpp',
+        'ftdc_system_stats.cpp',
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/base',
@@ -40,7 +48,7 @@ env.Library(
         '$BUILD_DIR/mongo/db/server_parameters',
         '$BUILD_DIR/mongo/db/storage/storage_options',
         'ftdc'
-    ],
+    ] + platform_libs,
 )
 
 env.CppUnitTest(
diff --git a/src/mongo/db/ftdc/ftdc_mongod.cpp b/src/mongo/db/ftdc/ftdc_mongod.cpp
index 13b353e76e3..6cbd781de3c 100644
--- a/src/mongo/db/ftdc/ftdc_mongod.cpp
+++ b/src/mongo/db/ftdc/ftdc_mongod.cpp
@@ -35,11 +35,11 @@
 #include "mongo/base/init.h"
 #include "mongo/base/status.h"
 #include "mongo/bson/bsonobjbuilder.h"
-
 #include "mongo/db/commands.h"
 #include "mongo/db/ftdc/collector.h"
 #include "mongo/db/ftdc/config.h"
 #include "mongo/db/ftdc/controller.h"
+#include "mongo/db/ftdc/ftdc_system_stats.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/repl/replication_coordinator.h"
 #include "mongo/db/repl/replication_coordinator_global.h"
@@ -283,7 +283,6 @@ private:
 
 }  // namespace
 
-
 // Register the FTDC system
 // Note: This must be run before the server parameters are parsed during startup
 // so that the FTDCController is initialized.
@@ -326,6 +325,9 @@ void startFTDC() {
                                                                        << "oplog.rs")));
     }
 
+    // Install System Metric Collector as a periodic collector
+    installSystemMetricsCollector(controller.get());
+
     // Install file rotation collectors
     // These are collected on each file rotation.
 
diff --git a/src/mongo/db/ftdc/ftdc_system_stats.cpp b/src/mongo/db/ftdc/ftdc_system_stats.cpp
new file mode 100644
index 00000000000..35764e7768f
--- /dev/null
+++ b/src/mongo/db/ftdc/ftdc_system_stats.cpp
@@ -0,0 +1,96 @@
+/**
+ * Copyright (C) 2016 MongoDB Inc.
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * 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 GNU Affero General 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 <string>
+#include <vector>
+
+#include "mongo/base/status.h"
+#include "mongo/base/string_data.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/db/ftdc/collector.h"
+#include "mongo/db/ftdc/controller.h"
+#include "mongo/stdx/memory.h"
+
+#ifdef __linux__
+#include "mongo/util/procparser.h"
+#endif
+
+namespace mongo {
+
+constexpr auto kSystemMetricsCollector = "systemMetrics";
+
+#ifdef __linux__
+static const std::vector<StringData> kCpuKeys{
+    "btime", "cpu", "ctxt", "processes", "procs_blocked", "procs_running"};
+
+/**
+ *  Collect metrics from the Linux /proc file system.
+ */
+class LinuxSystemMetricsCollector final : public FTDCCollectorInterface {
+public:
+    void collect(OperationContext* txn, BSONObjBuilder& builder) override {
+        {
+            BSONObjBuilder subObjBuilder(builder.subobjStart("cpu"));
+            processStatusErrors(
+                procparser::parseProcStatFile("/proc/stat", kCpuKeys, &subObjBuilder),
+                &subObjBuilder);
+            subObjBuilder.doneFast();
+        }
+    }
+
+    std::string name() const override {
+        return kSystemMetricsCollector;
+    }
+
+private:
+    /**
+     * Convert any errors we see into BSON for the user to see in the final FTDC document. It is
+     * acceptable for the proc parser to fail, but we do not want to shutdown the FTDC loop because
+     * of it. We assume that the BSONBuilder is not corrupt on non-OK Status but nothing else with
+     * regards to the final document output.
+     */
+    static void processStatusErrors(Status s, BSONObjBuilder* builder) {
+        if (!s.isOK()) {
+            builder->append("error", s.toString());
+        }
+    }
+};
+
+void installSystemMetricsCollector(FTDCController* controller) {
+    controller->addPeriodicCollector(stdx::make_unique<LinuxSystemMetricsCollector>());
+}
+
+#else
+
+void installSystemMetricsCollector(FTDCController* controller) {}
+
+#endif
+
+}  // namespace mongo
diff --git a/src/mongo/db/ftdc/ftdc_system_stats.h b/src/mongo/db/ftdc/ftdc_system_stats.h
new file mode 100644
index 00000000000..4d88b596da2
--- /dev/null
+++ b/src/mongo/db/ftdc/ftdc_system_stats.h
@@ -0,0 +1,38 @@
+/**
+ * Copyright (C) 2016 MongoDB Inc.
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * 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 GNU Affero General 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.
+ */
+
+namespace mongo {
+
+class FTDCController;
+
+/**
+ * Install a system metrics collector if it exists as a periodic collector.
+ */
+void installSystemMetricsCollector(FTDCController* controller);
+
+}  // namespace mongo