case CONNECTION:
            return "Close idle connections or increase the connection pool size";
        case MEMORY:
            return "Reduce buffer sizes or increase heap memory";
        case DISK_SPACE:
            return "Free up disk space or use a different location";
        case QUOTA:
            return "Contact administrator to increase quota limits";
        case LOCK:

        final long maxBytes = runtime.maxMemory();
        final long totalBytes = runtime.totalMemory();
        final long usedBytes = totalBytes - freeBytes;
        return "Mem:{used " + byteCountToDisplaySize(usedBytes) + ", heap " + byteCountToDisplaySize(totalBytes) + ", max "
                + byteCountToDisplaySize(maxBytes) + "}";
    }

    /**
     * Converts byte count to human-readable size format.
     *

import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for various potential implementations of {@code ByteSource.asCharSource(...).read()}.
 */
// These benchmarks allocate a lot of data so use a large heap
@VmOptions({"-Xms12g", "-Xmx12g", "-d64"})
@NullUnmarked
public class ByteSourceAsCharSourceReadBenchmark {
  enum ReadStrategy {
    TO_BYTE_ARRAY_NEW_STRING {
      @Override

        buf.append("\"jvm\":{");
        final JvmStats jvmStats = JvmStats.jvmStats();
        final Mem mem = jvmStats.getMem();
        buf.append("\"memory\":{");
        buf.append("\"heap\":{");
        append(buf, "used", () -> mem.getHeapUsed().getBytes()).append(',');
        append(buf, "committed", () -> mem.getHeapCommitted().getBytes()).append(',');

**Performance Issues**
- Increase thread pool size in SuggesterBuilder
- Optimize batch sizes for indexing operations
- Review OpenSearch cluster performance

**Memory Usage**
- Configure appropriate JVM heap settings
- Monitor index sizes and optimize mappings
- Use streaming for large data imports

### Debug Logging

Enable debug logging for detailed troubleshooting:

```java

        final long freeMemory = Runtime.getRuntime().freeMemory();
        final String msg = String.format(
                "%d words from %d %s: {\"time\":{\"parse\":%d,\"index\":%d},\"cpu\":%f,\"mem\":{\"heap\":\"%dmb\",\"used\":\"%dmb\"}}",
                items.length, size, type, parseTime, indexTime, cpuLoad, maxMemory / (1024 * 1024),
                (maxMemory - freeMemory) / (1024 * 1024));
        logger.info(msg);

    final Queue<IndexedIterator<T>> queue;

    MergingIterator(
        Iterable<? extends Iterator<? extends T>> iterators, Comparator<? super T> itemComparator) {
      // A comparator that's used by the heap, allowing the heap
      // to be sorted based on the top of each iterator, with insertion order as tiebreaker
      Comparator<IndexedIterator<T>> heapComparator =
          (o1, o2) ->
              ComparisonChain.start()

    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    int size = stream.readInt();
    init(16); // resist hostile attempts to allocate gratuitous heap
    Serialization.populateMap(this, stream, size);
  }

  // TODO(cpovirk): Should we have a serialVersionUID here?

   * *Map variants. This class is particularly hard to benchmark, because the benefit is not only in
   * less allocation, but also having the GC do less work to scan the heap because of fewer
   * references, which is particularly hard to quantify.
   */

  /** Creates an empty {@code CompactHashMap} instance. */
  public static <K extends @Nullable Object, V extends @Nullable Object>

    assertTrue(
        "BitArray.bitSize() must return a positive number, but was " + bitArray.bitSize(),
        bitArray.bitSize() > 0);

    // Ideally we would also test the bitSize() overflow of this BF, but it runs out of heap space
    // BloomFilter.create(Funnels.unencodedCharsFunnel(), 244412641, 1e-11);
  }

  /**
   * Asserts that {@link BloomFilter#approximateElementCount} is within 1 percent of the expected
   * value.
   */