| /* |
| * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved. |
| * Copyright (c) 2023, 2024, Red Hat Inc. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test id=Default |
| * @summary Test JVM large page setup (default options) |
| * @library /test/lib |
| * @requires os.family == "linux" |
| * @modules java.base/jdk.internal.misc |
| * java.management |
| * @run driver TestHugePageDecisionsAtVMStartup |
| */ |
| |
| /* |
| * @test id=LP_enabled |
| * @summary Test JVM large page setup (+LP) |
| * @library /test/lib |
| * @requires os.family == "linux" |
| * @modules java.base/jdk.internal.misc |
| * java.management |
| * @run driver TestHugePageDecisionsAtVMStartup -XX:+UseLargePages |
| */ |
| |
| /* |
| * @test id=THP_enabled |
| * @summary Test JVM large page setup (+THP) |
| * @library /test/lib |
| * @requires os.family == "linux" |
| * @library /test/lib |
| * @modules java.base/jdk.internal.misc |
| * java.management |
| * @run driver TestHugePageDecisionsAtVMStartup -XX:+UseTransparentHugePages |
| */ |
| |
| import jdk.test.lib.os.linux.HugePageConfiguration; |
| import jdk.test.lib.process.OutputAnalyzer; |
| import jdk.test.lib.process.ProcessTools; |
| import jtreg.SkippedException; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Set; |
| |
| public class TestHugePageDecisionsAtVMStartup { |
| |
| // End user warnings, printing with Xlog:pagesize at warning level, should be unconditional |
| static final String warningNoTHP = "[warning][pagesize] UseTransparentHugePages disabled, transparent huge pages are not supported by the operating system."; |
| static final String warningNoLP = "[warning][pagesize] UseLargePages disabled, no large pages configured and available on the system."; |
| |
| static final String buildSizeString(long l) { |
| String units[] = { "K", "M", "G" }; |
| long factor = 1024 * 1024 * 1024; |
| for (int i = 2; i >= 0; i--) { |
| if (l >= factor) { |
| return Long.toString(l / factor) + units[i]; |
| } |
| factor /= 1024; |
| } |
| return Long.toString(l) + "B"; |
| } |
| |
| static void testOutput(boolean useLP, boolean useTHP, OutputAnalyzer out, HugePageConfiguration configuration) { |
| |
| // Note: If something goes wrong, the JVM warns but continues, so we should never see an exit value != 0 |
| out.shouldHaveExitValue(0); |
| |
| // Explicit hugepages: |
| // Let X = the default hugepage size of the system (the one in /proc/meminfo). |
| // The JVM will cycle through page sizes, starting at X, down to the smallest hugepage size. |
| // |
| // Example 1: a system with 1GB and 2MB pages, the default hugepage size is 1GB (can only be done |
| // via kernel parameter). the JVM should first attempt to use 1GB pages, failing that should try 2MB, failing |
| // that give up and disable -UseLargePages. |
| // |
| // Example 1: same system, but the default hugepage size is 2MB. The JVM should not attempt to use 1GB pages. |
| // |
| // This picture gets more complex with -XX:LargePageSizeInBytes, which overrides the default |
| // large page size; but we ignore this for now (feel free to extend the test to cover LBSiB too). |
| |
| boolean haveUsableExplicitHugePages = false; |
| if (configuration.supportsExplicitHugePages()) { |
| long defaultLargePageSize = configuration.getExplicitDefaultHugePageSize(); |
| Set<HugePageConfiguration.ExplicitHugePageConfig> configs = configuration.getExplicitHugePageConfigurations(); |
| for (HugePageConfiguration.ExplicitHugePageConfig config: configs) { |
| if (config.pageSize <= defaultLargePageSize) { |
| if (config.nr_hugepages > 0 || config.nr_overcommit_hugepages > 0) { |
| haveUsableExplicitHugePages = true; break; |
| } |
| } |
| } |
| } |
| |
| if (useTHP && !useLP) { |
| useLP = true; // its implicit |
| } |
| |
| if (!useLP) { |
| out.shouldContain("[info][pagesize] Large page support disabled"); |
| } else if (useLP && !useTHP && |
| (!configuration.supportsExplicitHugePages() || !haveUsableExplicitHugePages)) { |
| out.shouldContain(warningNoLP); |
| } else if (useLP && useTHP && !configuration.supportsTHP()) { |
| out.shouldContain(warningNoTHP); |
| } else if (useLP && !useTHP && |
| configuration.supportsExplicitHugePages() && haveUsableExplicitHugePages) { |
| if (configuration.getExplicitAvailableHugePageNumber() == 0) { |
| throw new SkippedException("No usable explicit hugepages configured on the system, skipping test"); |
| } |
| out.shouldContain("[info][pagesize] Using the default large page size: " + buildSizeString(configuration.getExplicitDefaultHugePageSize())); |
| out.shouldContain("[info][pagesize] UseLargePages=1, UseTransparentHugePages=0"); |
| out.shouldContain("[info][pagesize] Large page support enabled"); |
| } else if (useLP && useTHP && configuration.supportsTHP()) { |
| long thpPageSize = configuration.getThpPageSizeOrFallback(); |
| String thpPageSizeString = buildSizeString(thpPageSize); |
| // We expect to see exactly two "Usable page sizes" : the system page size and the THP page size. The system |
| // page size differs, but its always in KB). |
| out.shouldContain("[info][pagesize] UseLargePages=1, UseTransparentHugePages=1"); |
| out.shouldMatch(".*\\[info]\\[pagesize] Large page support enabled. Usable page sizes: \\d+[kK], " + thpPageSizeString + ". Default large page size: " + thpPageSizeString + ".*"); |
| } |
| } |
| |
| public static void main(String[] extraOptions) throws Exception { |
| List<String> allOptions = new ArrayList<String>(); |
| if (extraOptions != null) { |
| allOptions.addAll(Arrays.asList(extraOptions)); |
| } |
| allOptions.add("-Xmx128m"); |
| allOptions.add("-Xlog:pagesize"); |
| allOptions.add("-version"); |
| |
| boolean useLP = allOptions.contains("-XX:+UseLargePages"); |
| boolean useTHP = allOptions.contains("-XX:+UseTransparentHugePages"); |
| System.out.println("useLP: " + useLP + " useTHP: " + useTHP); |
| |
| ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder(allOptions.toArray(new String[0])); |
| OutputAnalyzer output = new OutputAnalyzer(pb.start()); |
| output.reportDiagnosticSummary(); |
| HugePageConfiguration configuration = HugePageConfiguration.readFromOS(); |
| System.out.println("configuration read from OS:" + configuration); |
| |
| testOutput(useLP, useTHP, output, configuration); |
| } |
| } |
