alamb opened a new issue, #27330: URL: https://github.com/apache/datafusion/issues/27330
# Background A core value proposition for DataFusion is its performance. We have lots of [benchmarks](https://github.com/apache/datafusion/tree/main/benchmarks), but there are many real world use cases that are not covered. For example, queries on `STRUCT`s / LISTSs and other nested types, but there are many more. There are many people looking for ways to help, and I want optimization effort to go to workloads people actually run rather than over optimize benchmarks like ClickBench or random things. # Open Call / Request To that end, I this is an open call for **users** of DataFusion to file issues describing queries they would like to go faster. Obviously we will not be able to help everyone, however, supplying the information below I think will maximize the chance of making it happen. **Why**: Ensure DataFusion stays focused on real users and actual use cases. **Who**: Real users of DataFusion -- you are using DataFusion and would like some particular workload to go faster. **How**: Open a new issue with the following information # Format Please provide the following information, concisely (please don't dump multiple pages of AI generated spew with every imaginable detail 🙏 ). **Use case**: 1-2 sentences (max) describing how you are using DataFusion. Examples: "Log data analysis from Parquet files on S3", "Full text search engine on local Vortex files", etc. **Local reproducer**: 1. Data files. In order of preference: - a script that generates the data - a synthetic or anonymized sample with the same shape as your real data - a public URL to the files Ideally the data is no more than 10s of GB and the query runs in under a minute on a laptop. 2. A simple benchmark command (ideally a `.sql` file we can run in `datafusion-cli`) that runs against your data files. 3. 1-2 sentences explaining what the data and query mean in English (for example the [query descriptions in our current benchmarks](https://github.com/apache/datafusion/tree/main/benchmarks/queries/clickbench#extended-queries)) If you can not share data, the schema and `EXPLAIN ANALYZE` output may still be useful, but issues with a runnable reproducer are far more likely to get attention and be acted on. **Current performance**: 1. DataFusion version, and any non-default configuration settings 2. How you run DataFusion (e.g. SQL or dataframe, do you have custom optimzer rules, etc) 3. Hardware 4. Why you think it could be faster (for example, the time another engine takes, or a profile / explain plan showing where the time goes) **Restrictions**: 1. Only include 1 query or query pattern in each issue (not your whole workload, please) to keep the conversation focused. Then please post a link to the new ticket below. # For contributors If you are looking for a way to help, check out any usses The first thing is **not** to code (or have your agent code) Instead, you should reproduce reported performance and analyze where the time is going and post a writeup to the ticket. Please include flamegraphs, diagrams, etc , not walls of AI generated analysis. Then, explore possible optimizations (AI tools are great at this). Review each idea carefully, and if you find one that looks general and improves performance write it up (1 paragraph) explaining the high level optimization, why it works, and what classes of queries are affected. # Example Here is an example using ClickBench Q22. **Use case**: Web analytics over a single Parquet table (ClickBench `hits`). **Data**: 14 GB, 100M rows, 105 columns ```shell wget https://datasets.clickhouse.com/hits_compatible/hits.parquet ``` **Query** (`q22.sql`, run with `datafusion-cli -f q22.sql`): ```sql CREATE EXTERNAL TABLE hits STORED AS PARQUET LOCATION 'hits.parquet'; SELECT "SearchPhrase", MIN("URL"), MIN("Title"), COUNT(*) AS c, COUNT(DISTINCT "UserID") FROM hits WHERE "Title" LIKE '%Google%' AND "URL" NOT LIKE '%.google.%' AND "SearchPhrase" <> '' GROUP BY "SearchPhrase" ORDER BY c DESC LIMIT 10; ``` **How this matches my real use case**: TODO 1-2 sentences **DataFusion Version**: 56.0.0 -- 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]
