I wonder if the DataFusion project might be a more natural home for this functionality? UDFs are more of a query engine concept, whereas arrow-rs is more focused on purely physical execution?
On 28 June 2024 19:41:39 BST, Runji Wang <wangrunji0...@163.com> wrote: >Hi Felipe, > >Vectorization will be applied whenever possible. When all input and output >types of a function are primitive (int16, int32, int64, float32, float64) and >do not involve any Option or Result, the macro will automatically generate >code based on unary <https://docs.rs/arrow/latest/arrow/compute/fn.unary.html> >or binary <https://docs.rs/arrow/latest/arrow/compute/fn.binary.html> kernels, >which potentially allows for vectorization. > >Both examples you showed are not vectorized. The `div` function is due to the >Result output, while `gcd` is due to the loop in its implementation. However, >if the function is simple enough, like an `add` function: > >#[function("add(int, int) -> int")] >fn add(a: i32, b: i32) -> i32 { > a + b >} > >It can be auto-vectorized by llvm. > >Runji > > >On 2024/06/28 17:13:16 Felipe Oliveira Carvalho wrote: >> On Fri, Jun 28, 2024 at 11:07 AM Andrew Lamb <al...@influxdata.com> wrote: >> > >> > Hi Xuanwo, >> > >> > Sorry for the delay in responding. I think the ability to easily write >> > functions that "feel" like native functions in whatever language and be >> > able to generate arrow / vectorized versions of them is quite valuable. >> > This is my understanding of what this proposal is about. >> >> My understanding is that it's not vectorized. From the examples in >> risingwavelabs/arrow-udf, <https://github.com/risingwavelabs/arrow-udf> it >> looks like the macros generate code that gathers values from columns into >> local scalars that are passed as scalar parameters to user functions. Is >> the hope here that rustc/llvm will auto-vectorize the code? >> >> #[function("gcd(int, int) -> int")] >> fn gcd(mut a: i32, mut b: i32) -> i32 { >> while b != 0 { >> (a, b) = (b, a % b); >> } >> a >> } >> >> #[function("div(int, int) -> int")] >> fn div(x: i32, y: i32) -> Result<i32, &'static str> { >> if y == 0 { >> return Err("division by zero"); >> } >> Ok(x / y) >> } >> >> > I left some additional comments on the markdown. >> > >> > One thing that might be worth doing is articulate some other potential >> > locations for where the code might go. One option, as I think you propose, >> > is to make its own repository. Another option could be to donate the code >> > and put the various language bindings in the same repo as the arrow >> > language implementations (e.g arrow-rs, arrow for python, etc) which would >> > likely make it easier to maintain and discover. >> > >> > I am curious about what other devs / users feel about this? >> > >> > Andrew >> > >> > >> > >> > On Thu, Jun 20, 2024 at 3:04 AM Xuanwo <xu...@apache.org> wrote: >> > >> > > Hello, everyone. >> > > >> > > I start this thread to disscuss the donation of a User-Defined Function >> > > Framework for Apache Arrow. >> > > >> > > Feel free to review and leave your comments here. For live review, >> please >> > > visit: >> > > >> > > https://hackmd.io/@xuanwo/apache-arrow-udf >> > > >> > > The original content also pasted here for a quick reading: >> > > >> > > ------ >> > > >> > > ## Abstract >> > > >> > > Arrow UDF is a User-Defined Function Framework for Apache Arrow. >> > > >> > > ## Proposal >> > > >> > > Arrow UDF allows user to easily create and run user-defined functions >> > > (UDF) in Rust, Python, Java or JavaScript based on Apache Arrow. The >> > > functions can be executed natively, or in WebAssembly, or in a remote >> > > server via Arrow Flight. >> > > >> > > Arrow UDF was originally designed to be used by the RisingWave project >> but >> > > is now being used by Databend and several database startups. >> > > >> > > We believe that the Arrow UDF project will provide diversity value to >> the >> > > entire Arrow community. >> > > >> > > ## Background >> > > >> > > Arrow UDF is being developed by an open-source community from day one >> and >> > > is owned by RisingWaveLabs. The project has been launched in December >> 2023. >> > > >> > > ## Initial Goals >> > > >> > > By transferring ownership of the project to the Apache Arrow, Arrow UDF >> > > expects to ensure its neutrality and further encourage and facilitate >> the >> > > adoption of Arrow UDF by the community. >> > > >> > > ## Current Status >> > > >> > > Contributors: 5 >> > > >> > > Users: >> > > >> > > - [RisingWave]: A Distributed SQL Database for Stream Processing. >> > > - [Databend]: An open-source cloud data warehouse that serves as a >> > > cost-effective alternative to Snowflake. >> > > >> > > ## Documentation >> > > >> > > The document of Arrow UDF is hosted at >> > > https://docs.rs/arrow-udf/latest/arrow_udf/. >> > > >> > > ## Initial Source >> > > >> > > The project currently holds a GitHub repository and multiple packages: >> > > >> > > - https://github.com/risingwavelabs/arrow-udf >> > > >> > > Rust: >> > > >> > > - https://crates.io/arrow-udf/ >> > > - https://crates.io/arrow-udf-python/ >> > > - https://crates.io/arrow-udf-js/ >> > > - https://crates.io/arrow-udf-js-deno/ >> > > - https://crates.io/arrow-udf-wasm/ >> > > >> > > Python: >> > > >> > > - https://pypi.org/project/arrow-udf/ >> > > >> > > Those packge will retain its name, while the repository will be moved to >> > > apache org. >> > > >> > > ## Required Resources >> > > >> > > ### Mailing Lists >> > > >> > > We can reuse the existing mailing lists that arrow have. >> > > >> > > ### Git Repositories >> > > >> > > From >> > > >> > > - https://github.com/risingwavelabs/arrow-udf >> > > >> > > To >> > > >> > > - https://gitbox.apache.org/asf/repos/arrow-udf >> > > - https://github.com/apache/arrow-udf >> > > >> > > ### Issue Tracking >> > > >> > > The project would like to continue using GitHub Issues. >> > > >> > > ### Other Resources >> > > >> > > The project has already chosen GitHub actions as continuous integration >> > > tools. >> > > >> > > ## Initial Committers >> > > >> > > - Runji Wang wangrunji0...@163.com >> > > - Giovanny Gutiérrez >> > > - sundy-li sund...@apache.org >> > > - Xuanwo xua...@apache.org >> > > - Max Justus Spransy maxjus...@gmail.com >> > > >> > > [RisingWave]: https://github.com/risingwavelabs/risingwave >> > > [Databend]: https://github.com/datafuselabs/databend >> > > >> > > Xuanwo >> > > >>
