SERVER-16643 extend linux transparent huge pages to include 'defrag' parameter.

At startup under Linux, mongod will check the following files:

/sys/kernel/mm/transparent_hugepage/enabled
/sys/kernel/mm/transparent_hugepage/defrag

and produce a warning if either of these parameters are set to [always].

The recommended setting is [never] for both parameters. See:

http://docs.mongodb.org/manual/administration/production-notes/#recommended-configuration

1 files changed, 137 insertions, 0 deletions

diff --git a/src/mongo/db/startup_warnings_mongod_test.cpp b/src/mongo/db/startup_warnings_mongod_test.cpp
new file mode 100644
index 00000000000..633a38b811a
--- /dev/null
+++ b/src/mongo/db/startup_warnings_mongod_test.cpp
@@ -0,0 +1,137 @@
+/**
+ *    Copyright 2015 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 <fstream>
+#include <ostream>
+
+#include "mongo/db/startup_warnings_mongod.h"
+#include "mongo/unittest/temp_dir.h"
+#include "mongo/unittest/unittest.h"
+
+namespace {
+
+    using mongo::unittest::TempDir;
+
+    using namespace mongo;
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterInvalidDirectory) {
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("no_such_directory", "param");
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::NonExistentPath, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterInvalidFile) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterInvalidFile");
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::NonExistentPath, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterEmptyFile) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterInvalidFile");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream(filename.c_str());
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::FileStreamFailed, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterBlankLine) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterBlankLine");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream ofs(filename.c_str());
+            ofs << std::endl;
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::FailedToParse, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterInvalidFormat) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterBlankLine");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream ofs(filename.c_str());
+            ofs << "always madvise never" << std::endl;
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::FailedToParse, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterEmptyOpMode) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterEmptyOpMode");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream ofs(filename.c_str());
+            ofs << "always madvise [] never" << std::endl;
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::BadValue, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterUnrecognizedOpMode) {
+        TempDir tempDir(
+            "StartupWarningsMongodTest_ReadTransparentHugePagesParameterUnrecognizedOpMode");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream ofs(filename.c_str());
+            ofs << "always madvise never [unknown]" << std::endl;
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_NOT_OK(result.getStatus());
+        ASSERT_EQUALS(ErrorCodes::BadValue, result.getStatus().code());
+    }
+
+    TEST(StartupWarningsMongodTest, ReadTransparentHugePagesParameterValidFormat) {
+        TempDir tempDir("StartupWarningsMongodTest_ReadTransparentHugePagesParameterBlankLine");
+        {
+            std::string filename(tempDir.path() + "/param");
+            std::ofstream ofs(filename.c_str());
+            ofs << "always madvise [never]" << std::endl;
+        }
+        StatusWith<std::string> result =
+            StartupWarningsMongod::readTransparentHugePagesParameter("param", tempDir.path());
+        ASSERT_OK(result.getStatus());
+        ASSERT_EQUALS("never", result.getValue());
+    }
+
+}  // namespace