public long build(final int buildIndexBatchSize, final BuildIndexCallback callback) {
    // ... setup code ...
    
    db.scanBucket(db.getSchema().getBucketById(associatedBucketId).getName(), record -> {
        db.getIndexer().addToIndex(LSMTreeIndex.this, record.getIdentity(), (Document) record);
        total.incrementAndGet();
        
        // NO LOGGING HERE - could be processing for hours!
        
        if (total.get() % buildIndexBatchSize == 0) {
            db.getWrappedDatabaseInstance().commit();
            db.getWrappedDatabaseInstance().begin();
        }
        
        if (callback != null)
            callback.onDocumentIndexed((Document) record, total.get());
        
        return true;
    });
    
    // ... cleanup code ...
}

public long build(final int buildIndexBatchSize, final BuildIndexCallback callback) {
    checkIsValid();
    final AtomicLong total = new AtomicLong();
    final long LOG_INTERVAL = 10000; // Log every 10K records
    
    if (propertyNames == null || propertyNames.isEmpty())
        throw new IndexException("Cannot rebuild index '" + name + "' because metadata information are missing");
    
    final DatabaseInternal db = getDatabase();
    
    if (status.compareAndSet(INDEX_STATUS.AVAILABLE, INDEX_STATUS.UNAVAILABLE)) {
        
        LogManager.instance().log(this, Level.INFO, 
            "Building index '%s' on %d properties...", name, propertyNames.size());
        
        final long startTime = System.currentTimeMillis();
        
        db.scanBucket(db.getSchema().getBucketById(associatedBucketId).getName(), record -> {
            db.getIndexer().addToIndex(LSMTreeIndex.this, record.getIdentity(), (Document) record);
            total.incrementAndGet();
            
            // ADD: Periodic progress logging
            if (total.get() % LOG_INTERVAL == 0) {
                final long elapsed = System.currentTimeMillis() - startTime;
                final double rate = total.get() / (elapsed / 1000.0);
                LogManager.instance().log(this, Level.INFO, 
                    "Building index '%s': processed %d records (%.0f records/sec)...", 
                    name, total.get(), rate);
            }
            
            if (total.get() % buildIndexBatchSize == 0) {
                db.getWrappedDatabaseInstance().commit();
                db.getWrappedDatabaseInstance().begin();
            }
            
            if (callback != null)
                callback.onDocumentIndexed((Document) record, total.get());
            
            return true;
        });
        
        // ADD: Completion logging
        final long elapsed = System.currentTimeMillis...

</details>

- Fixes ArcadeData/arcadedb#2763

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