> > We could indeed split up libarrow into more shared libraries. This > would mean accepting a lot more maintenance effort though, on a team > that is already overburdened. I'm not too keen on that in the short > term.
Something for longer term to think about. What are you seeing as the added maintenance here? On Thu, Sep 19, 2019 at 5:38 PM Wes McKinney <wesmck...@gmail.com> wrote: > hi Micah, > > > On Thu, Sep 19, 2019 at 12:41 AM Micah Kornfield <emkornfi...@gmail.com> > wrote: > > > > > > > > * Should optional components be "opt in", "out out", or a mix? > > > Currently it's a mix, and that's confusing for people. I think we > > > should make them all "opt in". > > > > Agreed they should all be opt in by default. I think active developer > are > > quite adept at flipping the appropriate CMake flags. > > > > Cool. I opened a tracking JIRA > https://issues.apache.org/jira/browse/ARROW-6637 and attached many > issues. Sorry for the new JIRA flood > > > > > > * Do we want to bring the out-of-the-box core build down to zero > > > dependencies, including not depending on boost::filesystem and > > > possibly checking the compiled Flatbuffers files. > > > > While it may be > > > slightly more maintenance work, I think the optics of a > > > "dependency-free" core build would be beneficial and help the project > > > marketing-wise. > > > > I'm -.5 on checking in generated artifacts but this is mostly stylistic. > > In the case of flatbuffers it seems like we might be able to get-away > with > > vendoring since it should mostly be headers only. > > > > I would prefer to try come up with more granular components and be > > very conservative on what is "core". I think it should be possible have > a > > zero dependency build if only MemoryPool, Buffers, Arrays and > ArrayBuilders > > in a core package [1]. This combined with discussion Antoine started on > an > > ABI compatible C-layer would make basic inter-op within a process > > reasonable. Moving up the stack to IPC and files, there is probably a > way > > to package headers separately from implementations. This would allow > other > > projects wishing to integrate with Arrow to bring their own > implementations > > without the baggage of boost::filesystem. Would this leave anything > besides > > "flatbuffers" as a hard dependency to support IPC? > > > > We could indeed split up libarrow into more shared libraries. This > would mean accepting a lot more maintenance effort though, on a team > that is already overburdened. I'm not too keen on that in the short > term. > > > Thanks, > > Micah > > > > > > [1] It probably makes sense to go even further and separate out > MemoryPool > > and Buffer, so we can break the circular relationship between parquet and > > arrow. > > Don't think this is possible even then, particularly in light of my > recent work reading and writing Arrow columnar data "closer to the > metal" inside Parquet, yielding beneficial performance improvements. > > > > > On Wed, Sep 18, 2019 at 8:03 AM Wes McKinney <wesmck...@gmail.com> > wrote: > > > > > To be clear I think we should make these changes right after 0.15.0 is > > > released so we aren't playing whackamole with our packaging scripts. > > > I'm happy to take the lead on the work... > > > > > > On Wed, Sep 18, 2019 at 9:54 AM Antoine Pitrou <solip...@pitrou.net> > > > wrote: > > > > > > > > On Wed, 18 Sep 2019 09:46:54 -0500 > > > > Wes McKinney <wesmck...@gmail.com> wrote: > > > > > I think these are both interesting areas to explore further. I'd > like > > > > > to focus on the couple of immediate items I think we should address > > > > > > > > > > * Should optional components be "opt in", "out out", or a mix? > > > > > Currently it's a mix, and that's confusing for people. I think we > > > > > should make them all "opt in". > > > > > * Do we want to bring the out-of-the-box core build down to zero > > > > > dependencies, including not depending on boost::filesystem and > > > > > possibly checking the compiled Flatbuffers files. While it may be > > > > > slightly more maintenance work, I think the optics of a > > > > > "dependency-free" core build would be beneficial and help the > project > > > > > marketing-wise. > > > > > > > > > > Both of these issues must be addressed whether we undertake a Bazel > > > > > implementation or some other refactor of the C++ build system. > > > > > > > > I think checking in the Flatbuffers files (and also Protobuf and > Thrift > > > > where applicable :-)) would be fine. > > > > > > > > As for boost::filesystem, getting rid of it wouldn't be a huge task. > > > > Still worth deciding whether we want to prioritize development time > for > > > > it, because it's not entirely trivial either. > > > > > > > > Regards > > > > > > > > Antoine. > > > > > > > > > > > >
