Github user vkorukanti commented on a diff in the pull request: https://github.com/apache/drill/pull/185#discussion_r40982402 --- Diff: contrib/storage-hive/core/src/main/java/org/apache/drill/exec/store/hive/HiveScan.java --- @@ -319,16 +319,12 @@ public ScanStats getScanStats() { estRowCount = data/1024; } - // Hive's native reader is neither memory efficient nor fast. If the rowcount is below - // HIVE_SERDE_SCAN_OVERHEAD_FACTOR, make sure it is at least HIVE_SERDE_SCAN_OVERHEAD_FACTOR to enable the planner - // to choose HiveDrillNativeParquetScan. Due to the project on top of HiveDrillNativeParquetScan, we end up - // choosing the HiveScan instead of HiveDrillNativeParquetScan if the cost is too low. - if (estRowCount <= HIVE_SERDE_SCAN_OVERHEAD_FACTOR) { - estRowCount = HIVE_SERDE_SCAN_OVERHEAD_FACTOR; - } + // Hive's native reader is neither memory efficient nor fast. Increase the CPU cost + // by a factor to let the planner choose HiveDrillNativeScan over HiveScan with SerDes. + float cpuCost = 1 * HIVE_SERDE_SCAN_OVERHEAD_FACTOR; --- End diff -- Fixed in updated patch. --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastructure@apache.org or file a JIRA ticket with INFRA. ---