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GeezerVison is showing github.com — lmdbjava/src/main/java/org/lmdbjava/Verifier.java at master · lmdbjava/lmdbjava Expand file tree/ Copy pathVerifier.javaMore file actions 286 lines (256 loc) · 9.21 KB / Copy pathVerifier.javaFile metadata and controls286 lines (256 loc) · 9.21 KB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 /* * Copyright © 2016-2025 The LmdbJava Open Source Project * * Licensed 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.lmdbjava; import static java.nio.ByteOrder.BIG_ENDIAN; import static java.util.Objects.requireNonNull; import static org.lmdbjava.DbiFlags.MDB_CREATE; import java.nio.ByteBuffer; import java.util.ArrayList; import java.util.List; import java.util.Random; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicBoolean; import java.util.zip.CRC32; /** * Verifies correct operation of LmdbJava in a given environment. * * <p>Due to the large variety of operating systems and Java platforms typically used with LmdbJava, * this class provides a convenient verification of correct operating behavior through a potentially * long duration set of tests that carefully verify correct storage and retrieval of successively * larger database entries. * * <p>The verifier currently operates by incrementing a <code>long</code> identifier that * deterministically maps to a given {@link Dbi} and value size. The key is simply the <code>long * </code> identifier. The value commences with a CRC that includes the identifier and the random * bytes of the value. Each entry is written out, and then the prior entry is retrieved using its * key. The prior entry's value is evaluated for accuracy and then deleted. Transactions are * committed in batches to ensure successive transactions correctly retrieve the results of earlier * transactions. * * <p>Please note the verification approach may be modified in the future. * * <p>If an exception is raised by this class, please: * * <ol> * <li>Ensure the {@link Env} passed at construction time complies with the requirements specified * at {@link #Verifier(org.lmdbjava.Env)} * <li>Attempt to use a different file system to store the database (be especially careful to not * use network file systems, remote file systems, read-only file systems etc) * <li>Record the full exception message and stack trace, then run the verifier again to see if it * fails at the same or a different point * <li>Raise a ticket on the LmdbJava Issue Tracker that confirms the above details along with the * failing operating system and Java version * </ol> */ public final class Verifier implements Callable<Long> { /** Number of DBIs the created environment should allow. */ public static final int DBI_COUNT = 5; private static final int BATCH_SIZE = 64; private static final int BUFFER_LEN = 1_024 * BATCH_SIZE; private static final int CRC_LENGTH = Long.BYTES; private static final int KEY_LENGTH = Long.BYTES; private final byte[] ba = new byte[BUFFER_LEN]; private final CRC32 crc = new CRC32(); private final List<Dbi<ByteBuffer>> dbis = new ArrayList<>(DBI_COUNT); private final Env<ByteBuffer> env; private long id; private final ByteBuffer key = ByteBuffer.allocateDirect(KEY_LENGTH); private final AtomicBoolean proceed = new AtomicBoolean(true); private final Random rnd = new Random(); private Txn<ByteBuffer> txn; private final ByteBuffer val = ByteBuffer.allocateDirect(BUFFER_LEN); /** * Create an instance of the verifier. * * <p>The caller must provide an {@link Env} configured with a suitable local storage location, * maximum DBIs equal to {@link #DBI_COUNT}, and a map size large enough to accommodate the * intended verification duration. * * <p>ALL EXISTING DATA IN THE DATABASE WILL BE DELETED. The caller must not interact with the * <code>Env</code> in any way (eg querying, transactions etc) while the verifier is executing. * * @param env target that complies with the above requirements (required) */ public Verifier(final Env<ByteBuffer> env) { requireNonNull(env); this.env = env; key.order(BIG_ENDIAN); deleteDbis(); createDbis(); } /** * Run the verifier until {@link #stop()} is called or an exception occurs. * * <p>Successful return of this method indicates no faults were detected. If any fault was * detected the exception message will detail the exact point that the fault was encountered. * * @return number of database rows successfully verified */ @Override public Long call() { try { while (proceed.get()) { transactionControl(); write(id); if (id > 0) { fetchAndDelete(id - 1); } id++; } } finally { if (txn != null) { txn.close(); } } return id; } /** * Execute the verifier for the given duration. * * <p>This provides a simple way to execute the verifier for those applications which do not wish * to manage threads directly. * * @param duration amount of time to execute * @param unit units used to express the duration * @return number of database rows successfully verified */ public long runFor(final long duration, final TimeUnit unit) { final long deadline = System.currentTimeMillis() + unit.toMillis(duration); final ExecutorService es = Executors.newSingleThreadExecutor(); final Future<Long> future = es.submit(this); try { while (System.currentTimeMillis() < deadline && !future.isDone()) { Thread.sleep(unit.toMillis(1)); } } catch (final InterruptedException ignored) { } finally { stop(); } final long result; try { result = future.get(); } catch (final InterruptedException | ExecutionException ex) { throw new IllegalStateException(ex); } finally { es.shutdown(); } return result; } private void createDbis() { for (int i = 0; i < DBI_COUNT; i++) { dbis.add(env.openDbi(Verifier.class.getSimpleName() + i, MDB_CREATE)); } } private void deleteDbis() { for (final byte[] existingDbiName : env.getDbiNames()) { final Dbi<ByteBuffer> existingDbi = env.createDbi().setDbName(existingDbiName).withDefaultComparator().open(); try (Txn<ByteBuffer> txn = env.txnWrite()) { existingDbi.drop(txn, true); txn.commit(); } } } private void fetchAndDelete(final long forId) { final Dbi<ByteBuffer> dbi = getDbi(forId); updateKey(forId); final ByteBuffer fetchedValue; try { fetchedValue = dbi.get(txn, key); } catch (final LmdbException ex) { throw new IllegalStateException("DB get id=" + forId, ex); } if (fetchedValue == null) { throw new IllegalStateException("DB not found id=" + forId); } verifyValue(forId, fetchedValue); try { dbi.delete(txn, key); } catch (final LmdbException ex) { throw new IllegalStateException("DB del id=" + forId, ex); } } private Dbi<ByteBuffer> getDbi(final long forId) { return dbis.get((int) (forId % dbis.size())); } /** Request the verifier to stop execution. */ private void stop() { proceed.set(false); } private void transactionControl() { if (id % BATCH_SIZE == 0) { if (txn != null) { txn.commit(); txn.close(); } rnd.nextBytes(ba); txn = env.txnWrite(); } } private void updateKey(final long forId) { key.clear(); key.putLong(forId); key.flip(); } private void updateValue(final long forId) { final int rndSize = valueSize(forId); crc.reset(); crc.update((int) forId); crc.update(ba, CRC_LENGTH, rndSize); final long crcVal = crc.getValue(); val.clear(); val.putLong(crcVal); val.put(ba, CRC_LENGTH, rndSize); val.flip(); } private int valueSize(final long forId) { final int mod = (int) (forId % BATCH_SIZE); final int base = 1_024 * mod; final int value = base == 0 ? 512 : base; return value - CRC_LENGTH - KEY_LENGTH; // aim to minimise partial pages } private void verifyValue(final long forId, final ByteBuffer bb) { final int rndSize = valueSize(forId); final int expected = rndSize + CRC_LENGTH; if (bb.limit() != expected) { throw new IllegalStateException( "Limit error id=" + forId + " exp=" + expected + " limit=" + bb.limit()); } final long crcRead = bb.getLong(); crc.reset(); crc.update((int) forId); crc.update(bb); final long crcVal = crc.getValue(); if (crcRead != crcVal) { throw new IllegalStateException("CRC error id=" + forId); } } private void write(final long forId) { final Dbi<ByteBuffer> dbi = getDbi(forId); updateKey(forId); updateValue(forId); try { dbi.put(txn, key, val); } catch (final LmdbException ex) { throw new IllegalStateException("DB put id=" + forId, ex); } } } |
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