pan3793 opened a new issue, #3040: URL: https://github.com/apache/parquet-java/issues/3040
### Describe the bug, including details regarding any error messages, version, and platform. ### Background I get some data loss reports after upgrading the internal Spark's Parquet from 1.13.1 to 1.14.3, after some experiments, I believe this should be a bug on the Parquet side, and it could be worked around by disabling `spark.sql.parquet.filterPushdown`. ### Analysis With some debugging, I think the issue was introduced by PARQUET-2432(https://github.com/apache/parquet-java/pull/1278). The issue is, during the evaluation of `DictionaryFilter.canDrop`(this happens when reading a column that has `PLAIN_DICTIONARY` with pushed predications), when dict size exceeds 8k, only the head 8k was copied https://github.com/apache/parquet-java/blob/274dc51bc9e5cc880ba3c77c3db826d2a4943965/parquet-hadoop/src/main/java/org/apache/parquet/hadoop/DictionaryPageReader.java#L113 the correct data ``` ... |00001fd0| 34 32 35 34 30 39 0a 00 00 00 37 32 39 33 39 38 |425409....729398| |00001fe0| 39 35 33 30 0a 00 00 00 39 38 32 30 31 36 39 36 |9530....98201696| |00001ff0| 34 34 0a 00 00 00 37 33 39 31 32 34 37 38 30 36 |44....7391247806| |00002000| 0b 00 00 00 31 32 35 32 35 31 36 31 34 31 36 0a |....12525161416.| |00002010| 00 00 00 38 37 38 35 35 34 34 36 34 35 0b 00 00 |...8785544645...| |00002020| 00 31 32 32 38 30 38 37 35 39 30 32 0b 00 00 00 |.12280875902....| ... ``` the copied data ``` ... |00001fd0| 34 32 35 34 30 39 0a 00 00 00 37 32 39 33 39 38 |425409....729398| |00001fe0| 39 35 33 30 0a 00 00 00 39 38 32 30 31 36 39 36 |9530....98201696| |00001ff0| 34 34 0a 00 00 00 37 33 39 31 32 34 37 38 30 36 |44....7391247806| |00002000| 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| |00002010| 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| |00002020| 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| ... ``` the root cause is https://github.com/apache/parquet-java/blob/274dc51bc9e5cc880ba3c77c3db826d2a4943965/parquet-common/src/main/java/org/apache/parquet/bytes/BytesInput.java#L379 may not read fully if the underlying `InputStream`'s `available` method always returns 0 ``` private static class ReadableByteChannelImpl extends AbstractInterruptibleChannel // Not really interruptible implements ReadableByteChannel { ... private static final int TRANSFER_SIZE = 8192; public int read(ByteBuffer dst) throws IOException { if (!isOpen()) { throw new ClosedChannelException(); } int len = dst.remaining(); int totalRead = 0; int bytesRead = 0; synchronized (readLock) { while (totalRead < len) { int bytesToRead = Math.min((len - totalRead), TRANSFER_SIZE); if (buf.length < bytesToRead) buf = new byte[bytesToRead]; if ((totalRead > 0) && !(in.available() > 0)) break; // block at most once try { begin(); bytesRead = in.read(buf, 0, bytesToRead); } finally { end(bytesRead > 0); } if (bytesRead < 0) break; else totalRead += bytesRead; dst.put(buf, 0, bytesRead); } if ((bytesRead < 0) && (totalRead == 0)) return -1; return totalRead; } } ... } ``` ### Component(s) Core -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
