I would resist using a checked exception. We would end up having to add it to almost everything everywhere. Or constantly wrapping it with RuntimeException to get around that; in which case why make it checked to begin with?
On Tue, Jun 30, 2015 at 1:28 PM, Hanifi GUNES <h...@apache.org> wrote: > I would propose throwing a checked exception encouraging explicit and > consistent handling of this event. Each sub-system has liberty to decide if > an OOM failure is fatal or non-fatal depending on its capabilities. Also if > at some point a sub-system needs to communicate with its callers via a > different mechanism such like using flags (boolean, enum etc) or raising an > unchecked exception that's still fine, just handle the exception. If there > is a need to suppress the checked exception that's fine too, just use a > helper method. > > Either way, returning *null* sounds problematic in many ways i) it is > implicit ii) unsafe iii) its handling logic is repetitive iv) it is > semantically unclean to make null mean something - even worse something > context specific. > > > -Hanifi > > 2015-06-30 12:23 GMT-07:00 Abdel Hakim Deneche <adene...@maprtech.com>: > > > I guess that would fix the issue too. But we may still run into > situations > > where the caller will pass a flag to "mute" the exception and not handle > > the case anyway. > > > > If .buffer() unconditionally throws an exception, can't the caller, who > > wants to, just catch that and handle it properly ? > > > > On Tue, Jun 30, 2015 at 12:13 PM, Chris Westin <chriswesti...@gmail.com> > > wrote: > > > > > No, but we should do something close to that. > > > > > > There are cases where the caller can handle the inability to get more > > > memory, and may be able to go to disk. However, you are correct that > > there > > > are many that can't handle an OOM, and that fail to check. > > > > > > Instead of unconditionally throwing OutOfMemoryRuntimeException, I > would > > > suggest that the buffer() call take a flag that indicates whether or > not > > it > > > should throw if it is unable to fulfill the request. This way, the call > > > sites that can handle an OOM can pass in the flag to return null, and > the > > > rest can pass in the flag value to throw, and not have to have any > > checking > > > code. > > > > > > > > > On Tue, Jun 30, 2015 at 12:06 PM, Abdel Hakim Deneche < > > > adene...@maprtech.com > > > > wrote: > > > > > > > our current implementations of BufferAllocator.buffer(int, int) > returns > > > > null when it cannot allocate the buffer. > > > > > > > > But looking through the code, there are many places that don't check > if > > > the > > > > allocated buffer is null before trying to access it which will throw > a > > > > NullPointerException. > > > > > > > > ValueVectors' allocateNewSafe() seem to be the only place that handle > > the > > > > null in a specific manner. > > > > > > > > Should we update the allocators' implementation to throw an > > > > OutOfMemoryRuntimeException instead of returning null ? this has the > > > added > > > > benefit of displaying a proper out of memory error message to the > user. > > > > > > > > Thanks! > > > > > > > > -- > > > > > > > > Abdelhakim Deneche > > > > > > > > Software Engineer > > > > > > > > <http://www.mapr.com/> > > > > > > > > > > > > Now Available - Free Hadoop On-Demand Training > > > > < > > > > > > > > > > http://www.mapr.com/training?utm_source=Email&utm_medium=Signature&utm_campaign=Free%20available > > > > > > > > > > > > > > > > > > > > -- > > > > Abdelhakim Deneche > > > > Software Engineer > > > > <http://www.mapr.com/> > > > > > > Now Available - Free Hadoop On-Demand Training > > < > > > http://www.mapr.com/training?utm_source=Email&utm_medium=Signature&utm_campaign=Free%20available > > > > > >
