Ah yes, and no more saving the main session :) > FWIW - I noticed that the DataFlow Options documentation[1] for setting the pickling library and the Beam documentation
Thanks for bringing it up. The doc is outdated, the issue was fixed in https://github.com/apache/beam/issues/21615 . On Wed, Apr 30, 2025 at 6:28 AM Joey Tran <joey.t...@schrodinger.com> wrote: > Wow this is fantastic! I tested it out and it worked great for my runner. > I am also excited for this change now and will eagerly set `cloudpickle` as > the default pickler for our code. > > FWIW - I noticed that the DataFlow Options documentation[1] for setting > the pickling library and the Beam documentation [2] for setting the > pickling library differ slightly. The DataFlow documentation mentions > having to set `pickler.set_library(pickler.USE_CLOUDPICKLE)` while the Beam > documentation doesn't say anything about that. It turned out unnecessary > for my runner - not sure if it's just a DataFlow runner specific > requirement, but just wanted to point it out. > > [1] > https://cloud.google.com/dataflow/docs/reference/pipeline-options#pythonyaml > [2] > https://beam.apache.org/documentation/sdks/python-pipeline-dependencies/#pickling-and-managing-the-main-session > > On Wed, Apr 30, 2025 at 2:38 AM Robert Bradshaw <rober...@waymo.com> > wrote: > >> On Tue, Apr 29, 2025 at 7:51 PM Joey Tran <joey.t...@schrodinger.com> >> wrote: >> > >> > Does cloudpickle make --save_main_session unnecessary? As in, will more >> transforms defined in __main__ "just work"? >> >> Yes. Or at least it "just works" much more often. (There may still be >> corner cases, but I haven't run into them...) >> >> I, for one, am excited to see this change. Thanks, Claude, for taking >> the lead on this. >> >> > If so, I can see why that's worthwhile. I've had a _ton_ of issues with >> this, especially with new users of beam at my company. Explaining main >> session and why random things throw unpickling errors or why their >> transform is throwing Name errors has been a very painful experience, >> especially since it usually happens with users first experiences >> > >> > On Tue, Apr 29, 2025, 6:14 PM Valentyn Tymofieiev via dev < >> dev@beam.apache.org> wrote: >> >> >> >> There are several reasons: >> >> - wide adoption in data processing community , see initial >> discussion: [1] >> >> - expectations on cloudpickle having a larger number of maintainers >> and contributors. >> >> - new releases of dill had breaking changes[2], which made adoption >> of a new version challenging. >> >> - cloudpickle is easier to vendor - it is a single file and unlike >> dill, does not create side-effects in the global namespace, which might >> conflict with any unvendored version. vendoring allows to eliminate a >> common failure mode when the pickler library is different at submission and >> runtime. >> >> - previously, some bugs and feature requests Beam requested in dill >> took a long time to be implemented and released. >> >> >> >> [1] https://lists.apache.org/thread/dvxvclhok0fx48955x6szvw4kotxh87n >> >> [2] >> https://github.com/apache/beam/issues/22893#issuecomment-1502354194 >> >> >> >> On Mon, Apr 28, 2025 at 4:00 PM Joey Tran <joey.t...@schrodinger.com> >> wrote: >> >>> >> >>> Naive question, but why is beam upgrading to cloudpickle? >> >>> >> >>> I saw this doc: >> >>> >> https://docs.google.com/document/d/1G5Q0ckX5sKQRQD1yEkLCPQL7N6B-AL9Cb1p0zlOOfQU/edit?tab=t.0 >> >>> >> >>> Is the main reason because cloudpickle is more actively maintained? >> >>> >> >>> >> >>> On Mon, Apr 28, 2025 at 6:51 PM Claudius van der Merwe < >> claud...@vdmza.com> wrote: >> >>>> >> >>>> Hi Beam Devs, >> >>>> >> >>>> >> >>>> I am making progress on making cloudpickle the default pickling >> library and removing the strict dependency on dill as outlined in >> https://s.apache.org/beam-cloudpickle-next-steps. >> >>>> >> >>>> >> >>>> The current plan is to: >> >>>> >> >>>> >> >>>> 1. Make cloudpickle the default library in Beam 2.65.0 release (see >> https://github.com/apache/beam/pull/34695). Users will be able to >> specify pickle_library='dill' without any additional requirements. There >> will still be a hard dependency on dill (blocked by #2) but it is a step in >> the right direction. >> >>>> >> >>>> >> >>>> 2. Remove the strict dependency on dill in Beam 2.66.0 release. Dill >> is directly used for coder's encoding types in FastPrimitivesCoderImpl >> [1][2]. I prefer to submit a fix for this after the branch cut so we have >> more time to identify any issues. >> >>>> >> >>>> >> >>>> Coudpickle has some fundamentally different pickling behavior to >> dill that is likely to break: >> >>>> >> >>>> Unittests that rely on globals >> >>>> >> >>>> This can be fixed by using apache_beam.utils.shared [3] >> >>>> >> >>>> Closures and dynamic classes that reference unpicklable globals >> >>>> >> >>>> This can be fixed by defining functions in the top level, and using >> functools.partial to bind parameters if necessary >> >>>> >> >>>> >> >>>> [1] >> https://github.com/apache/beam/blob/b9fa49a9827dd28349e382f479ebd1a8bbe27d07/sdks/python/apache_beam/coders/coder_impl.py#L529 >> >>>> >> >>>> [2] >> https://github.com/apache/beam/blob/b9fa49a9827dd28349e382f479ebd1a8bbe27d07/sdks/python/apache_beam/coders/coder_impl.py#L595 >> >>>> >> >>>> [3] >> https://github.com/apache/beam/blob/b9fa49a9827dd28349e382f479ebd1a8bbe27d07/sdks/python/apache_beam/internal/cloudpickle_pickler_test.py#L54 >> >>>> >> >>>> >> >>>> I'd appreciate any feedback or concerns. >> >>>> >> >>>> >> >>>> Best, >> >>>> >> >>>> Claude >> >>>> >> >>>> >> >
