[jira] [Resolved] (SPARK-12007) Network library's RPC layer requires a lot of copying

["Andrew Or (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/SPARK-12007?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Andrew Or resolved SPARK-12007.
-------------------------------
       Resolution: Fixed
    Fix Version/s: 1.6.0

> Network library's RPC layer requires a lot of copying
> -----------------------------------------------------
>
>                 Key: SPARK-12007
>                 URL: https://issues.apache.org/jira/browse/SPARK-12007
>             Project: Spark
>          Issue Type: Improvement
>          Components: Spark Core
>    Affects Versions: 1.6.0
>            Reporter: Marcelo Vanzin
>            Assignee: Marcelo Vanzin
>             Fix For: 1.6.0
>
>
> The network library's RPC layer has an external API based on byte arrays, instead of ByteBuffer; that requires a lot of copying since the internals of the library use ByteBuffers (or rather Netty's ByteBuf), and lots of external clients also use ByteBuffer.
> The extra copies could be avoided if the API used ByteBuffer instead.
> To show an extreme case, look at an RPC send via NettyRpcEnv:
> - message is encoded using JavaSerializer, resulting in a ByteBuffer
> - the ByteBuffer is copied into a byte array of the right size, since its internal array may be larger than the actual data it holds
> - the network library's encoder copies the byte array into a ByteBuf
> - finally the data is written to the socket
> The intermediate 2 copies could be avoided if the API allowed the original ByteBuffer to be sent instead.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org