parthchandra commented on PR #968: URL: https://github.com/apache/parquet-mr/pull/968#issuecomment-1136552664
> This is interesting, because when I did profiling of Trino, I found that although I/O (from S3, over the network no less) was significant, even more time was spent in compute. Maybe you're getting improved performance because you're increasing _parallelism_ between I/O and compute. It may be because I was using Spark's vectorized parquet decoding which is an order or magnitude faster than parquet library's row by row decoding (see [Spark benchmarks](https://github.com/apache/spark/blob/master/sql/core/benchmarks/DataSourceReadBenchmark-results.txt)). If trino is not doing vectorized decoding (I took a very quick look and I don't think it is), I would suggest you can look into that next. All the cool kids are doing it. -- 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