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Java TestHFileWriterV2.randomRowOrQualifier方法代码示例

本文整理汇总了Java中org.apache.hadoop.hbase.io.hfile.TestHFileWriterV2.randomRowOrQualifier方法的典型用法代码示例。如果您正苦于以下问题:Java TestHFileWriterV2.randomRowOrQualifier方法的具体用法?Java TestHFileWriterV2.randomRowOrQualifier怎么用?Java TestHFileWriterV2.randomRowOrQualifier使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在org.apache.hadoop.hbase.io.hfile.TestHFileWriterV2的用法示例。


在下文中一共展示了TestHFileWriterV2.randomRowOrQualifier方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Java代码示例。

示例1: readStoreFile

import org.apache.hadoop.hbase.io.hfile.TestHFileWriterV2; //导入方法依赖的package包/类
private void readStoreFile(int t, BloomType bt, List<KeyValue> kvs,
    Path sfPath) throws IOException {
  StoreFile sf = new StoreFile(fs, sfPath, conf, cacheConf, bt);
  StoreFile.Reader r = sf.createReader();
  final boolean pread = true; // does not really matter
  StoreFileScanner scanner = r.getStoreFileScanner(true, pread);

  {
    // Test for false negatives (not allowed).
    int numChecked = 0;
    for (KeyValue kv : kvs) {
      byte[] row = kv.getRow();
      boolean present = isInBloom(scanner, row, kv.getQualifier());
      assertTrue(testIdMsg + " Bloom filter false negative on row "
          + Bytes.toStringBinary(row) + " after " + numChecked
          + " successful checks", present);
      ++numChecked;
    }
  }

  // Test for false positives (some percentage allowed). We test in two modes:
  // "fake lookup" which ignores the key distribution, and production mode.
  for (boolean fakeLookupEnabled : new boolean[] { true, false }) {
    ByteBloomFilter.setFakeLookupMode(fakeLookupEnabled);
    try {
      String fakeLookupModeStr = ", fake lookup is " + (fakeLookupEnabled ?
          "enabled" : "disabled");
      CompoundBloomFilter cbf = (CompoundBloomFilter) r.getGeneralBloomFilter();
      cbf.enableTestingStats();
      int numFalsePos = 0;
      Random rand = new Random(EVALUATION_SEED);
      int nTrials = NUM_KV[t] * 10;
      for (int i = 0; i < nTrials; ++i) {
        byte[] query = TestHFileWriterV2.randomRowOrQualifier(rand);
        if (isInBloom(scanner, query, bt, rand)) {
          numFalsePos += 1;
        }
      }
      double falsePosRate = numFalsePos * 1.0 / nTrials;
      LOG.debug(String.format(testIdMsg
          + " False positives: %d out of %d (%f)",
          numFalsePos, nTrials, falsePosRate) + fakeLookupModeStr);

      // Check for obvious Bloom filter crashes.
      assertTrue("False positive is too high: " + falsePosRate + " (greater "
          + "than " + TOO_HIGH_ERROR_RATE + ")" + fakeLookupModeStr,
          falsePosRate < TOO_HIGH_ERROR_RATE);

      // Now a more precise check to see if the false positive rate is not
      // too high. The reason we use a relaxed restriction for the real-world
      // case as opposed to the "fake lookup" case is that our hash functions
      // are not completely independent.

      double maxZValue = fakeLookupEnabled ? 1.96 : 2.5;
      validateFalsePosRate(falsePosRate, nTrials, maxZValue, cbf,
          fakeLookupModeStr);

      // For checking the lower bound we need to eliminate the last chunk,
      // because it is frequently smaller and the false positive rate in it
      // is too low. This does not help if there is only one under-sized
      // chunk, though.
      int nChunks = cbf.getNumChunks();
      if (nChunks > 1) {
        numFalsePos -= cbf.getNumPositivesForTesting(nChunks - 1);
        nTrials -= cbf.getNumQueriesForTesting(nChunks - 1);
        falsePosRate = numFalsePos * 1.0 / nTrials;
        LOG.info(testIdMsg + " False positive rate without last chunk is " +
            falsePosRate + fakeLookupModeStr);
      }

      validateFalsePosRate(falsePosRate, nTrials, -2.58, cbf,
          fakeLookupModeStr);
    } finally {
      ByteBloomFilter.setFakeLookupMode(false);
    }
  }

  r.close(true); // end of test so evictOnClose
}
 
开发者ID:fengchen8086,项目名称:ditb,代码行数:80,代码来源:TestCompoundBloomFilter.java

示例2: readStoreFile

import org.apache.hadoop.hbase.io.hfile.TestHFileWriterV2; //导入方法依赖的package包/类
private void readStoreFile(int t, BloomType bt, List<KeyValue> kvs,
    Path sfPath) throws IOException {
  StoreFile sf = new StoreFile(fs, sfPath, conf, cacheConf, bt,
      NoOpDataBlockEncoder.INSTANCE);
  StoreFile.Reader r = sf.createReader();
  final boolean pread = true; // does not really matter
  StoreFileScanner scanner = r.getStoreFileScanner(true, pread);

  {
    // Test for false negatives (not allowed).
    int numChecked = 0;
    for (KeyValue kv : kvs) {
      byte[] row = kv.getRow();
      boolean present = isInBloom(scanner, row, kv.getQualifier());
      assertTrue(testIdMsg + " Bloom filter false negative on row "
          + Bytes.toStringBinary(row) + " after " + numChecked
          + " successful checks", present);
      ++numChecked;
    }
  }

  // Test for false positives (some percentage allowed). We test in two modes:
  // "fake lookup" which ignores the key distribution, and production mode.
  for (boolean fakeLookupEnabled : new boolean[] { true, false }) {
    ByteBloomFilter.setFakeLookupMode(fakeLookupEnabled);
    try {
      String fakeLookupModeStr = ", fake lookup is " + (fakeLookupEnabled ?
          "enabled" : "disabled");
      CompoundBloomFilter cbf = (CompoundBloomFilter) r.getGeneralBloomFilter();
      cbf.enableTestingStats();
      int numFalsePos = 0;
      Random rand = new Random(EVALUATION_SEED);
      int nTrials = NUM_KV[t] * 10;
      for (int i = 0; i < nTrials; ++i) {
        byte[] query = TestHFileWriterV2.randomRowOrQualifier(rand);
        if (isInBloom(scanner, query, bt, rand)) {
          numFalsePos += 1;
        }
      }
      double falsePosRate = numFalsePos * 1.0 / nTrials;
      LOG.debug(String.format(testIdMsg
          + " False positives: %d out of %d (%f)",
          numFalsePos, nTrials, falsePosRate) + fakeLookupModeStr);

      // Check for obvious Bloom filter crashes.
      assertTrue("False positive is too high: " + falsePosRate + " (greater "
          + "than " + TOO_HIGH_ERROR_RATE + ")" + fakeLookupModeStr,
          falsePosRate < TOO_HIGH_ERROR_RATE);

      // Now a more precise check to see if the false positive rate is not
      // too high. The reason we use a relaxed restriction for the real-world
      // case as opposed to the "fake lookup" case is that our hash functions
      // are not completely independent.

      double maxZValue = fakeLookupEnabled ? 1.96 : 2.5;
      validateFalsePosRate(falsePosRate, nTrials, maxZValue, cbf,
          fakeLookupModeStr);

      // For checking the lower bound we need to eliminate the last chunk,
      // because it is frequently smaller and the false positive rate in it
      // is too low. This does not help if there is only one under-sized
      // chunk, though.
      int nChunks = cbf.getNumChunks();
      if (nChunks > 1) {
        numFalsePos -= cbf.getNumPositivesForTesting(nChunks - 1);
        nTrials -= cbf.getNumQueriesForTesting(nChunks - 1);
        falsePosRate = numFalsePos * 1.0 / nTrials;
        LOG.info(testIdMsg + " False positive rate without last chunk is " +
            falsePosRate + fakeLookupModeStr);
      }

      validateFalsePosRate(falsePosRate, nTrials, -2.58, cbf,
          fakeLookupModeStr);
    } finally {
      ByteBloomFilter.setFakeLookupMode(false);
    }
  }

  r.close(true); // end of test so evictOnClose
}
 
开发者ID:fengchen8086,项目名称:LCIndex-HBase-0.94.16,代码行数:81,代码来源:TestCompoundBloomFilter.java


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