Ivan Vergiliev created SPARK-5269: ------------------------------------- Summary: BlockManager.dataDeserialize always creates a new serializer instance Key: SPARK-5269 URL: https://issues.apache.org/jira/browse/SPARK-5269 Project: Spark Issue Type: Improvement Components: Spark Core Reporter: Ivan Vergiliev
BlockManager.dataDeserialize always creates a new instance of the serializer, which is pretty slow in some cases. I'm using Kryo serialization and have a custom registrator, and its register method is showing up as taking about 15% of the execution time in my profiles. This started happening after I increased the number of keys in a job with a shuffle phase by a factor of 40. One solution I can think of is to create a ThreadLocal SerializerInstance for the defaultSerializer, and only create a new one if a custom serializer is passed in. AFAICT a custom serializer is passed only from DiskStore.getValues, and that, on the other hand, depends on the serializer passed to ExternalSorter. I don't know how often this is used, but I think this can still be a good solution for the standard use case. Oh, and also - ExternalSorter already has a SerializerInstance, so if the getValues method is called from a single thread, maybe we can pass that directly? I'd be happy to try a patch but would probably need a confirmation from someone that this approach would indeed work (or an idea for another). -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org