diff --git a/velox/connectors/Connector.h b/velox/connectors/Connector.h
index cd9ab91fb59e..1a659df964a1 100644
--- a/velox/connectors/Connector.h
+++ b/velox/connectors/Connector.h
@@ -175,6 +175,8 @@ class DataSource {
   // Returns the number of input bytes processed so far.
   virtual uint64_t getCompletedBytes() = 0;
 
+  virtual uint64_t getFileSize() { return 0; }
+
   // Returns the number of input rows processed so far.
   virtual uint64_t getCompletedRows() = 0;
 
diff --git a/velox/connectors/hive/HiveDataSource.cpp b/velox/connectors/hive/HiveDataSource.cpp
index a3f8308488e0..af00ad01faed 100644
--- a/velox/connectors/hive/HiveDataSource.cpp
+++ b/velox/connectors/hive/HiveDataSource.cpp
@@ -414,9 +414,17 @@ HiveDataSource::HiveDataSource(
   SubfieldFilters filters;
   core::TypedExprPtr remainingFilter;
   if (hiveTableHandle->isFilterPushdownEnabled()) {
+    std::ostringstream oss;
+    oss << "collect ";
     for (auto& [k, v] : hiveTableHandle->subfieldFilters()) {
+      oss << k.toString() << " -> " << v->toString() << "\n";
       filters.emplace(k.clone(), v->clone());
     }
+
+    std::cout << "[zcw] " << oss.str();
+    std::cout << "[zcw] remainingFilter:"
+              << hiveTableHandle->remainingFilter()->toString() << std::endl;
+
     remainingFilter = extractFiltersFromRemainingFilter(
         hiveTableHandle->remainingFilter(),
         expressionEvaluator_,
@@ -434,6 +442,11 @@ HiveDataSource::HiveDataSource(
     }
   }
 
+  for (auto& [k, v] : filters) {
+    std::cout << "[zcw] iterator " << k.toString() << " -> " << v->toString()
+              << "\n";
+  }
+
   auto outputTypes = outputType_->children();
   readerOutputType_ = ROW(std::move(columnNames), std::move(outputTypes));
   scanSpec_ = makeScanSpec(
@@ -443,6 +456,9 @@ HiveDataSource::HiveDataSource(
       remainingFilterInputs,
       pool_);
 
+  std::cout << "[zcw] readerOutputType_:" << readerOutputType_->toString()
+            << std::endl;
+
   if (remainingFilter) {
     metadataFilter_ = std::make_shared<common::MetadataFilter>(
         *scanSpec_, *remainingFilter, expressionEvaluator_);
@@ -474,6 +490,12 @@ HiveDataSource::HiveDataSource(
   rowReaderOpts_.setScanSpec(scanSpec_);
   rowReaderOpts_.setMetadataFilter(metadataFilter_);
 
+  std::cout << "[zcw] fileSchema:" << readerOpts_.getFileSchema()->toString()
+            << " readerOutputType_:" << readerOutputType_->toString()
+            << " remainingFilterInputs size:" << remainingFilterInputs.size()
+            << " filter.size:" << filters.size() << " filterPushdownEnabled:"
+            << hiveTableHandle->isFilterPushdownEnabled() << std::endl;
+
   ioStats_ = std::make_shared<dwio::common::IoStatistics>();
 }
 
@@ -486,6 +508,8 @@ void HiveDataSource::addSplit(std::shared_ptr<ConnectorSplit> split) {
 
   VLOG(1) << "Adding split " << split_->toString();
 
+  std::cout << "[zcw] add split:" << split_->filePath << std::endl;
+
   fileHandle_ = fileHandleFactory_->generate(split_->filePath).second;
   auto input = createBufferedInput(*fileHandle_, readerOpts_);
 
@@ -499,6 +523,8 @@ void HiveDataSource::addSplit(std::shared_ptr<ConnectorSplit> split) {
     readerOpts_.setFileFormat(split_->fileFormat);
   }
 
+  std::cout << "[zcw] " << readerOpts_.toString() << std::endl;
+
   reader_ = dwio::common::getReaderFactory(readerOpts_.getFileFormat())
                 ->createReader(std::move(input), readerOpts_);
 
@@ -781,6 +807,7 @@ HiveDataSource::createBufferedInput(
     const FileHandle& fileHandle,
     const dwio::common::ReaderOptions& readerOpts) {
   if (auto* asyncCache = dynamic_cast<cache::AsyncDataCache*>(allocator_)) {
+    std::cout << "[zcw] AsyncDataCache CachedBufferedInput" << std::endl;
     return std::make_unique<dwio::common::CachedBufferedInput>(
         fileHandle.file,
         readerOpts.getMemoryPool(),
@@ -794,6 +821,9 @@ HiveDataSource::createBufferedInput(
         readerOpts.loadQuantum(),
         readerOpts.maxCoalesceDistance());
   }
+
+  std::cout << "[zcw] BufferedInput, name:" << fileHandle.file->getName()
+            << std::endl;
   return std::make_unique<dwio::common::BufferedInput>(
       fileHandle.file,
       readerOpts.getMemoryPool(),
diff --git a/velox/connectors/hive/HiveDataSource.h b/velox/connectors/hive/HiveDataSource.h
index 2dc448d13699..806a244fe263 100644
--- a/velox/connectors/hive/HiveDataSource.h
+++ b/velox/connectors/hive/HiveDataSource.h
@@ -56,6 +56,10 @@ class HiveDataSource : public DataSource {
     return ioStats_->rawBytesRead();
   }
 
+  uint64_t getFileSize() override {
+    return ioStats_->fileSize_;
+  }
+
   uint64_t getCompletedRows() override {
     return completedRows_;
   }
diff --git a/velox/dwio/common/InputStream.cpp b/velox/dwio/common/InputStream.cpp
index 65a040742cd8..d492694c0216 100644
--- a/velox/dwio/common/InputStream.cpp
+++ b/velox/dwio/common/InputStream.cpp
@@ -60,7 +60,9 @@ ReadFileInputStream::ReadFileInputStream(
     const MetricsLogPtr& metricsLog,
     IoStatistics* stats)
     : InputStream(readFile->getName(), metricsLog, stats),
-      readFile_(std::move(readFile)) {}
+      readFile_(std::move(readFile)) {
+  stats->fileSize_ += getLength();
+}
 
 void ReadFileInputStream::read(
     void* buf,
diff --git a/velox/dwio/common/IoStatistics.cpp b/velox/dwio/common/IoStatistics.cpp
index 8774900d247c..2bab81db4cb0 100644
--- a/velox/dwio/common/IoStatistics.cpp
+++ b/velox/dwio/common/IoStatistics.cpp
@@ -95,6 +95,7 @@ IoStatistics::operationStats() const {
 }
 
 void IoStatistics::merge(const IoStatistics& other) {
+  fileSize_ += other.fileSize_;
   rawBytesRead_ += other.rawBytesRead_;
   rawBytesWritten_ += other.rawBytesWritten_;
   totalScanTime_ += other.totalScanTime_;
diff --git a/velox/dwio/common/IoStatistics.h b/velox/dwio/common/IoStatistics.h
index d4508eb53a08..9bab7660c703 100644
--- a/velox/dwio/common/IoStatistics.h
+++ b/velox/dwio/common/IoStatistics.h
@@ -114,7 +114,8 @@ class IoStatistics {
 
   folly::dynamic getOperationStatsSnapshot() const;
 
- private:
+ //private:
+  std::atomic<uint64_t> fileSize_{0};
   std::atomic<uint64_t> rawBytesRead_{0};
   std::atomic<uint64_t> rawBytesWritten_{0};
   std::atomic<uint64_t> inputBatchSize_{0};
diff --git a/velox/dwio/common/Options.h b/velox/dwio/common/Options.h
index 523f136e6e70..c31b97f087fa 100644
--- a/velox/dwio/common/Options.h
+++ b/velox/dwio/common/Options.h
@@ -376,6 +376,16 @@ class ReaderOptions {
   uint64_t filePreloadThreshold{kDefaultFilePreloadThreshold};
   bool fileColumnNamesReadAsLowerCase = false;
 
+  std::string toString() const {
+    std::ostringstream oss;
+    oss << "[ReaderOptions] autoPreloadLength:" << autoPreloadLength
+        << " prefetchMode:" << (int)prefetchMode
+        << " loadQuantum_:" << (int)loadQuantum_
+        << " directorySizeGuess:" << directorySizeGuess
+        << " filePreloadThreshold:" << filePreloadThreshold;
+    return oss.str();
+  }
+
  public:
   static constexpr int32_t kDefaultLoadQuantum = 8 << 20; // 8MB
   static constexpr int32_t kDefaultCoalesceDistance = 512 << 10; // 512K
diff --git a/velox/dwio/dwrf/reader/ReaderBase.cpp b/velox/dwio/dwrf/reader/ReaderBase.cpp
index 640842d79504..8ce64b0e20b7 100644
--- a/velox/dwio/dwrf/reader/ReaderBase.cpp
+++ b/velox/dwio/dwrf/reader/ReaderBase.cpp
@@ -207,6 +207,9 @@ ReaderBase::ReaderBase(
 
   if (!cache_ && input_->shouldPrefetchStripes()) {
     auto numStripes = getFooter().stripesSize();
+    std::cout << "[zcw] shouldPrefetchStripes, numStripes:" << numStripes
+              << std::endl;
+
     for (auto i = 0; i < numStripes; i++) {
       const auto stripe = getFooter().stripes(i);
       input_->enqueue(
@@ -219,6 +222,12 @@ ReaderBase::ReaderBase(
     }
   }
 
+  std::cout << "[zcw] fileLength:" << fileLength_ << " psLength:" << psLength_
+            << " footerSize:" << footerSize << " cacheSize:" << cacheSize
+            << " tailSize:" << tailSize
+            << " shouldPreftchStripes:" << input_->shouldPrefetchStripes()
+            << " readSize:" << readSize << std::endl;
+
   // initialize file decrypter
   handler_ = DecryptionHandler::create(*footer_, decryptorFactory_.get());
 }
diff --git a/velox/exec/Operator.cpp b/velox/exec/Operator.cpp
index 2614a1b63857..36c62cb15041 100644
--- a/velox/exec/Operator.cpp
+++ b/velox/exec/Operator.cpp
@@ -350,6 +350,8 @@ void OperatorStats::add(const OperatorStats& other) {
   inputPositions += other.inputPositions;
   inputVectors += other.inputVectors;
 
+  fileSize += other.fileSize;
+
   getOutputTiming.add(other.getOutputTiming);
   outputBytes += other.outputBytes;
   outputPositions += other.outputPositions;
diff --git a/velox/exec/Operator.h b/velox/exec/Operator.h
index 4dcf9b9ea480..0ec68974666d 100644
--- a/velox/exec/Operator.h
+++ b/velox/exec/Operator.h
@@ -98,6 +98,8 @@ struct OperatorStats {
   uint64_t rawInputBytes = 0;
   uint64_t rawInputPositions = 0;
 
+  uint64_t fileSize = 0;
+
   CpuWallTiming addInputTiming;
 
   /// Bytes of input in terms of retained size of input vectors.
diff --git a/velox/exec/PlanNodeStats.cpp b/velox/exec/PlanNodeStats.cpp
index 053604c05cce..1153ea496458 100644
--- a/velox/exec/PlanNodeStats.cpp
+++ b/velox/exec/PlanNodeStats.cpp
@@ -39,6 +39,8 @@ void PlanNodeStats::addTotals(const OperatorStats& stats) {
   rawInputRows += stats.rawInputPositions;
   rawInputBytes += stats.rawInputBytes;
 
+  fileSize += stats.fileSize;
+
   outputRows += stats.outputPositions;
   outputBytes += stats.outputBytes;
   outputVectors += stats.outputVectors;
diff --git a/velox/exec/PlanNodeStats.h b/velox/exec/PlanNodeStats.h
index 11de5f127e5c..43465ab69122 100644
--- a/velox/exec/PlanNodeStats.h
+++ b/velox/exec/PlanNodeStats.h
@@ -62,6 +62,8 @@ struct PlanNodeStats {
   /// Sum of raw input bytes for all corresponding operators.
   uint64_t rawInputBytes{0};
 
+  uint64_t fileSize{0};
+
   /// Sum of output rows for all corresponding operators. When
   /// plan node corresponds to multiple operator types, operators of only one of
   /// these types report non-zero output rows.
diff --git a/velox/exec/TableScan.cpp b/velox/exec/TableScan.cpp
index 089468907e03..6a92b6fef4bc 100644
--- a/velox/exec/TableScan.cpp
+++ b/velox/exec/TableScan.cpp
@@ -47,6 +47,8 @@ TableScan::TableScan(
                          ->queryConfig()
                          .preferredOutputBatchRows()) {
   connector_ = connector::getConnector(tableHandle_->connectorId());
+
+  std::cout << "[zcw] ==== " << toString() << " ====" << std::endl;
 }
 
 RowVectorPtr TableScan::getOutput() {
@@ -107,6 +109,8 @@ RowVectorPtr TableScan::getOutput() {
             tableHandle_,
             columnHandles_,
             connectorQueryCtx_.get());
+        std::cout << "[zcw] pendingDynamicFilters_.size="
+                  << pendingDynamicFilters_.size() << std::endl;
         for (const auto& entry : pendingDynamicFilters_) {
           dataSource_->addDynamicFilter(entry.first, entry.second);
         }
@@ -135,6 +139,7 @@ RowVectorPtr TableScan::getOutput() {
           VELOX_CHECK(operatorCtx_->task()->isCancelled());
           return nullptr;
         }
+        std::cout << "[zcw] setFromDataSource\n";
         dataSource_->setFromDataSource(std::move(preparedDataSource));
       } else {
         dataSource_->addSplit(connectorSplit);
@@ -178,6 +183,11 @@ RowVectorPtr TableScan::getOutput() {
 
       lockedStats->rawInputPositions = dataSource_->getCompletedRows();
       lockedStats->rawInputBytes = dataSource_->getCompletedBytes();
+      lockedStats->fileSize = dataSource_->getFileSize();
+
+      std::cout << "[zcw] fileSize:" << lockedStats->fileSize
+                << " rawInputBytes:" << lockedStats->rawInputBytes << std::endl;
+
       auto data = dataOptional.value();
       if (data) {
         if (data->size() > 0) {