+1 I think some people might already mistake the startBundle()/finishBundle() methods for what the new methods are supposed to be
On Tue, 28 Jun 2016 at 19:38 Raghu Angadi <[email protected]> wrote: > This is terrific! > Thanks for the proposal. > > On Tue, Jun 28, 2016 at 9:06 AM, Thomas Groh <[email protected]> > wrote: > > > Hey Everyone: > > > > We've recently started to be permitted to reuse DoFn instances in > Beam[1]. > > Beyond the efficiency gains from not having to deserialize new DoFn > > instances for every bundle, DoFn reuse also provides the ability to > > minimize expensive setup work done per-bundle, which hasn't formerly been > > possible. Additionally, it has also enabled more failure cases, where > > element-based state leaks improperly across bundles. > > > > I've written a document proposing that two methods are added to the API > of > > DoFn, setup and teardown, which both provides hooks for users to write > > efficient DoFns, as well as signals that DoFns will be reused. > > > > The document is located at > > > > > https://docs.google.com/document/d/1LLQqggSePURt3XavKBGV7SZJYQ4NW8yCu63lBchzMRk/edit?ts=5771458f# > > and committers have edit access > > > > Thanks, > > > > Thomas > > > > [1] https://github.com/apache/incubator-beam/pull/419 > > >
