parthchandra commented on code in PR #999: URL: https://github.com/apache/parquet-mr/pull/999#discussion_r997548363
########## parquet-hadoop/src/main/java/org/apache/parquet/hadoop/ParquetFileReader.java: ########## @@ -1093,10 +1099,38 @@ private ColumnChunkPageReadStore internalReadFilteredRowGroup(BlockMetaData bloc } } } - // actually read all the chunks + // Vectored IO up. + + List<FileRange> ranges = new ArrayList<>(); for (ConsecutivePartList consecutiveChunks : allParts) { - consecutiveChunks.readAll(f, builder); + ranges.add(FileRange.createFileRange(consecutiveChunks.offset, (int) consecutiveChunks.length)); + } + LOG.warn("Doing vectored IO for ranges {}", ranges); + f.readVectored(ranges, ByteBuffer::allocate); Review Comment: > Don't you think it is similar to what I have done in the commented readVectored() implementation? Yes, it is. However, the parallel reading will split a large range as opposed to what the vectored read will do. > I guess we need to run some benchmarks. First, I need to see what type of ranges parquet generates for real-world/tpcds queries. Do you have that by any chance? No I don't have the ranges. TPCDS is a large set of queries. Pick a scale factor and a couple of queries and I'll see what I can get for you. -- 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: dev-unsubscr...@parquet.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org