Hi Yuta, It seems Chesnay is right. The "fallback" in flink's documentation is in terms of the types flink supported. But for all the other arbitrary types kryo is the first choice.
2018-07-12 9:55 GMT+08:00 Yuta Morisawa <yu-moris...@kddi-research.jp>: > Thank you for your answer. > > > For POJOs Flink has a custom serializer. For arbitrary objects we use > > kryo, and can use Avro as a fallback. > https://ci.apache.org/projects/flink/flink-docs-release-1.5/ > dev/types_serialization.html#serialization-of-pojo-types > > It may be the reverse. > Kryo is for fallback, right? > > > On 2018/07/11 19:00, Chesnay Schepler wrote: > >> 1) TypeInformation are used to create serializers, comparators and to >> verify correctness of certain operations (like projections on tuple >> datasets). >> >> 2) see https://flink.apache.org/news/2015/05/11/Juggling-with-Bits- >> and-Bytes.html >> >> 3) Flink comes with a number of serializers for varying types as outlined >> here <https://ci.apache.org/projects/flink/flink-docs-release-1. >> 5/dev/types_serialization.html#flinks-typeinformation-class>. >> For POJOs Flink has a custom serializer. For arbitrary objects we use >> kryo, and can use Avro as a fallback. >> >> On 11.07.2018 09:24, Yuta Morisawa wrote: >> >>> Hi all >>> >>> Now, I'm reading Flink document and I have some points to feel difficult >>> to get an idea. >>> I'd appreciate if you tell it me. >>> >>> 1,TypeInformation >>> I understand TypeInformation is used for selecting relevant serializer >>> and comparator. >>> But, the ducument doesn't specify if it has another way to be used. >>> >>> So, what I want to know is that what kinds of process gets benefit from >>> TypeInformation other than serializer and comparator. >>> >>> 2, Managed Memory >>> The word "Managed memory" is appeared several time in the document but >>> I can't find any detail description. >>> This is the only document I found (https://www.slideshare.net/sb >>> altagi/overview-of-apacheflinkbyslimbaltagi) >>> >>> If anyone has document that explains managed memory, please let me know. >>> >>> 3, Serializer >>> What do the words in the document "serializers we ship with Flink" >>> mean? I know Flink uses avro for POJOs, is it the same thing? >>> https://ci.apache.org/projects/flink/flink-docs-release-1.5/ >>> dev/types_serialization.html >>> >>> >>> Regards, >>> Yuta >>> >>> >> >
