I agree with Stephan that a simple on/off configuration option for local recovery would be easier to understand and gives more flexibility wrt future changes.
Cheers, Till On Sun, May 13, 2018 at 4:00 PM, sihua zhou <summerle...@163.com> wrote: > +1 for @Stephan's proposal, it makes the out of the box experience better > and also leaves some space for the expert. > > Best, > Sihua > > > > On 05/12/2018 02:41，Stephan Ewen<se...@apache.org> <se...@apache.org> > wrote： > > Hi! > > The configuration option (in flink-conf.yaml) for local recovery is > currently an enumeration with the values "DISABLED" and > "ENABLE_FILE_BASED". > > I would suggest to change that, for a few reasons: > > - Having values like "ENABLE_FILE_BASED" breaks with the style of the > other config options. Having a homogeneous feel for the configuration of > the system is important for ease of use. > > - Do we need to require users to understand what file-based local > recovery means? It might be easier for users to have an option to activate > deactivate the mode (on by default in the future) and if we need to have > different modes in the future, then we can have a "mode" option as an > "expert option". That way we expose the simple fact of whether to use local > recovery or not in a simple boolean, and hide the complex tuning part > (which hopefully few users ever need to touch) in a separate option. > > - Are we sure already whether options beyond "on/off" are shared across > state backends? For example, memory snapshot based local recovery would be > specific to the Memoy/FsStateBackend. Persistent-volume based local > recovery may behave differently for RocksDB and FsStateBackend. > > > ==> This config option looks like it sets things up in a tricky direction. > We can still change it, now that we have not yet released it. > > Best, > Stephan > >
