[
https://issues.apache.org/jira/browse/HIVE-25827?focusedWorklogId=781628&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-781628
]
ASF GitHub Bot logged work on HIVE-25827:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 15/Jun/22 12:52
Start Date: 15/Jun/22 12:52
Worklog Time Spent: 10m
Work Description: pvary commented on code in PR #3368:
URL: https://github.com/apache/hive/pull/3368#discussion_r897940618
##########
ql/src/java/org/apache/hadoop/hive/ql/io/parquet/ParquetRecordReaderBase.java:
##########
@@ -48,115 +49,133 @@
import java.util.List;
import java.util.Map;
-public class ParquetRecordReaderBase {
+public abstract class ParquetRecordReaderBase {
public static final Logger LOG =
LoggerFactory.getLogger(ParquetRecordReaderBase.class);
- protected Path file;
+ protected final FileSplit fileSplit;
+ protected Path filePath;
+ protected ParquetInputSplit parquetInputSplit;
+ protected ParquetMetadata parquetMetadata;
protected ProjectionPusher projectionPusher;
protected boolean skipTimestampConversion = false;
protected Boolean skipProlepticConversion;
protected Boolean legacyConversionEnabled;
protected SerDeStats serDeStats;
- protected JobConf jobConf;
+ protected final JobConf jobConf;
protected int schemaSize;
- protected List<BlockMetaData> filtedBlocks;
+ protected List<BlockMetaData> filteredBlocks;
protected ParquetFileReader reader;
+ protected ParquetRecordReaderBase(JobConf conf, InputSplit oldSplit) throws
IOException {
+ serDeStats = new SerDeStats();
+ projectionPusher = new ProjectionPusher();
+
+ if (!(oldSplit instanceof FileSplit)) {
+ throw new IllegalArgumentException("Unknown split type: " + oldSplit);
+ }
+ this.fileSplit = (FileSplit) oldSplit;
+ this.jobConf = projectionPusher.pushProjectionsAndFilters(conf,
fileSplit.getPath().getParent());
+ this.filePath = fileSplit.getPath();
+ }
+
+ protected void setupMetadataAndParquetSplit(JobConf conf) throws IOException
{
+ // In the case of stat tasks a dummy split is created with -1 length but
real path...
+ if (fileSplit.getLength() != 0) {
+ parquetMetadata = getParquetMetadata(filePath, conf);
+ parquetInputSplit = getSplit(conf);
+ }
+ // having null as parquetInputSplit seems to be a valid case based on this
file's history
+ }
+
/**
* gets a ParquetInputSplit corresponding to a split given by Hive
*
- * @param oldSplit The split given by Hive
* @param conf The JobConf of the Hive job
* @return a ParquetInputSplit corresponding to the oldSplit
* @throws IOException if the config cannot be enhanced or if the footer
cannot be read from the file
*/
@SuppressWarnings("deprecation")
protected ParquetInputSplit getSplit(
- final org.apache.hadoop.mapred.InputSplit oldSplit,
final JobConf conf
) throws IOException {
- if (oldSplit.getLength() == 0) {
- return null;
- }
+
ParquetInputSplit split;
- if (oldSplit instanceof FileSplit) {
- final Path finalPath = ((FileSplit) oldSplit).getPath();
- jobConf = projectionPusher.pushProjectionsAndFilters(conf,
finalPath.getParent());
-
- // TODO enable MetadataFilter by using readFooter(Configuration
configuration, Path file,
- // MetadataFilter filter) API
- final ParquetMetadata parquetMetadata =
ParquetFileReader.readFooter(jobConf, finalPath);
- final List<BlockMetaData> blocks = parquetMetadata.getBlocks();
- final FileMetaData fileMetaData = parquetMetadata.getFileMetaData();
-
- final ReadSupport.ReadContext
- readContext = new DataWritableReadSupport().init(new
InitContext(jobConf,
- null, fileMetaData.getSchema()));
-
- // Compute stats
- for (BlockMetaData bmd : blocks) {
- serDeStats.setRowCount(serDeStats.getRowCount() + bmd.getRowCount());
- serDeStats.setRawDataSize(serDeStats.getRawDataSize() +
bmd.getTotalByteSize());
- }
+ final Path finalPath = fileSplit.getPath();
Review Comment:
Could you please help me highlighting the changes here which are not just
changes in indentation?
Issue Time Tracking
-------------------
Worklog Id: (was: 781628)
Time Spent: 40m (was: 0.5h)
> Parquet file footer is read multiple times, when multiple splits are created
> in same file
> -----------------------------------------------------------------------------------------
>
> Key: HIVE-25827
> URL: https://issues.apache.org/jira/browse/HIVE-25827
> Project: Hive
> Issue Type: Improvement
> Reporter: Rajesh Balamohan
> Assignee: Ádám Szita
> Priority: Major
> Labels: performance, pull-request-available
> Attachments: image-2021-12-21-03-19-38-577.png
>
> Time Spent: 40m
> Remaining Estimate: 0h
>
> With large files, it is possible that multiple splits are created in the same
> file. With current codebase, "ParquetRecordReaderBase" ends up reading file
> footer for each split.
> It can be optimized not to read footer information multiple times for the
> same file.
>
> [https://github.com/apache/hive/blob/master/ql/src/java/org/apache/hadoop/hive/ql/io/parquet/vector/VectorizedParquetRecordReader.java#L160]
>
> [https://github.com/apache/hive/blob/master/ql/src/java/org/apache/hadoop/hive/ql/io/parquet/ParquetRecordReaderBase.java#L91]
>
>
> !image-2021-12-21-03-19-38-577.png|width=1363,height=1256!
>
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