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[Bootstrap] Throw exception if the JVM will corrupt data.
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Detect the worst-offenders, all IBM versions and several known hotspot
versions that can cause index corruption, and fail on startup.

Provide/detect compiler workarounds when they exist, but warn about
performance degradation.

In all cases the check can be bypassed completely with a safety
switch via undocumented system property (es.bypass.vm.check=true)

Closes #7580
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rmuir committed Mar 21, 2015
1 parent b184541 commit 8d4c805
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4 changes: 4 additions & 0 deletions src/main/java/org/elasticsearch/bootstrap/Bootstrap.java
Expand Up @@ -206,6 +206,10 @@ public static void main(String[] args) {
Loggers.disableConsoleLogging();
System.out.close();
}

// fail if using broken version
JVMCheck.check();

bootstrap.setup(true, tuple);

stage = "Startup";
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139 changes: 139 additions & 0 deletions src/main/java/org/elasticsearch/bootstrap/JVMCheck.java
@@ -0,0 +1,139 @@
/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/

package org.elasticsearch.bootstrap;

import org.apache.lucene.util.Constants;
import org.elasticsearch.common.logging.Loggers;

import java.lang.management.ManagementFactory;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/** Checks that the JVM is ok and won't cause index corruption */
public class JVMCheck {

/**
* URL with latest JVM recommendations
*/
static final String JVM_RECOMMENDATIONS = "http://www.elastic.co/guide/en/elasticsearch/reference/current/_installation.html";

/**
* System property which if set causes us to bypass the check completely (but issues a warning in doing so)
*/
static final String JVM_BYPASS = "es.bypass.vm.check";

/**
* Metadata and messaging for hotspot bugs.
*/
static class HotspotBug {

/** OpenJDK bug URL */
final String bugUrl;

/** Compiler workaround flag (null if there is no workaround) */
final String workAround;

HotspotBug(String bugUrl, String workAround) {
this.bugUrl = bugUrl;
this.workAround = workAround;
}

/** Returns an error message to the user for a broken version */
String getErrorMessage() {
StringBuilder sb = new StringBuilder();
sb.append("Java version: ").append(Constants.JAVA_VERSION);
sb.append(" suffers from critical bug ").append(bugUrl);
sb.append(" which can cause data corruption.");
sb.append(System.lineSeparator());
sb.append("Please upgrade the JVM, see ").append(JVM_RECOMMENDATIONS);
sb.append(" for current recommendations.");
if (workAround != null) {
sb.append(System.lineSeparator());
sb.append("If you absolutely cannot upgrade, please add ").append(workAround);
sb.append(" to the JVM_OPTS environment variable.");
sb.append(System.lineSeparator());
sb.append("Upgrading is preferred, this workaround will result in degraded performance.");
}
return sb.toString();
}

/** Warns the user when a workaround is being used to dodge the bug */
String getWarningMessage() {
StringBuilder sb = new StringBuilder();
sb.append("Workaround flag ").append(workAround);
sb.append(" for bug ").append(bugUrl);
sb.append(" found. ");
sb.append(System.lineSeparator());
sb.append("This will result in degraded performance!");
sb.append(System.lineSeparator());
sb.append("Upgrading is preferred, see ").append(JVM_RECOMMENDATIONS);
sb.append(" for current recommendations.");
return sb.toString();
}
}

/** mapping of hotspot version to hotspot bug information for the most serious bugs */
static final Map<String,HotspotBug> JVM_BROKEN_HOTSPOT_VERSIONS;

static {
Map<String,HotspotBug> bugs = new HashMap<>();

// 1.7.0: loop optimizer bug
bugs.put("21.0-b17", new HotspotBug("https://bugs.openjdk.java.net/browse/JDK-7070134", "-XX:-UseLoopPredicate"));
// register allocation issues (technically only x86/amd64). This impacted update 40, 45, and 51
bugs.put("24.0-b56", new HotspotBug("https://bugs.openjdk.java.net/browse/JDK-8024830", "-XX:-UseSuperWord"));
bugs.put("24.45-b08", new HotspotBug("https://bugs.openjdk.java.net/browse/JDK-8024830", "-XX:-UseSuperWord"));
bugs.put("24.51-b03", new HotspotBug("https://bugs.openjdk.java.net/browse/JDK-8024830", "-XX:-UseSuperWord"));

JVM_BROKEN_HOTSPOT_VERSIONS = Collections.unmodifiableMap(bugs);
}

/**
* Checks that the current JVM is "ok". This means it doesn't have severe bugs that cause data corruption.
*/
static void check() {
if (Boolean.parseBoolean(System.getProperty(JVM_BYPASS))) {
Loggers.getLogger(JVMCheck.class).warn("bypassing jvm version check for version [{}], this can result in data corruption!", Constants.JAVA_VERSION);
} else if ("Oracle Corporation".equals(Constants.JVM_VENDOR)) {
HotspotBug bug = JVM_BROKEN_HOTSPOT_VERSIONS.get(Constants.JVM_VERSION);
if (bug != null) {
if (bug.workAround != null && ManagementFactory.getRuntimeMXBean().getInputArguments().contains(bug.workAround)) {
Loggers.getLogger(JVMCheck.class).warn(bug.getWarningMessage());
} else {
throw new RuntimeException(bug.getErrorMessage());
}
}
} else if ("IBM Corporation".equals(Constants.JVM_VENDOR)) {
// currently any JVM from IBM will easily result in index corruption.
StringBuilder sb = new StringBuilder();
sb.append("IBM runtimes suffer from several bugs which can cause data corruption.");
sb.append(System.lineSeparator());
sb.append("Please upgrade the JVM, see ").append(JVM_RECOMMENDATIONS);
sb.append(" for current recommendations.");
throw new RuntimeException(sb.toString());
}
}

/** Command line driver for convenience */
public static void main(String args[]) {
check();
}
}

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