[
https://issues.apache.org/jira/browse/CASSANDRA-8100?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
C. Scott Andreas updated CASSANDRA-8100:
----------------------------------------
Component/s: Streaming and Messaging
> Remove payload size from intra-cluster messages
> -----------------------------------------------
>
> Key: CASSANDRA-8100
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8100
> Project: Cassandra
> Issue Type: Improvement
> Components: Streaming and Messaging
> Reporter: Sylvain Lebresne
> Priority: Major
> Fix For: 4.x
>
>
> Intra-cluster messages ship with the [size of their
> payload|https://github.com/apache/cassandra/blob/8d8fed52242c34b477d0384ba1d1ce3978efbbe8/src/java/org/apache/cassandra/net/MessageOut.java#L118]
> before said payload. We mostly don't need it however as deserializers don't
> rely on it to know when to stop. The [only reason we need
> it|https://github.com/apache/cassandra/blob/8d8fed52242c34b477d0384ba1d1ce3978efbbe8/src/java/org/apache/cassandra/net/MessageIn.java#L86]
> is that all responses message use the same {{Verb}} and so in those case we
> use the message callback to find out the proper serializer, but in the
> (unlikely) case where the callback has expired, we don't know which
> deserializer to use and so we use the payload size to skip the payload.
> Having to ship the payload size means we need to be able to compute it. Which
> means we have to implement the serializedSize for all of your serializer (not
> a huge deal but annoying), but more importantly, this makes it impossible to
> write a request response truly incrementally (CASSANDRA-8099) since you have
> to buffer everything in memory just to compute the serialized size.
> So I propose we remove the payload size from messages. Instead, we can assign
> specific {{Verb}} to each response type (getting rid of
> {{CallbackDeterminedSerializer}}). We can then get rid of all the
> serializedSize methods (for upgrade, when we need to generate messages to old
> nodes, we could just write the message in a ByteBuffer, write the resulting
> size and then write the buffer).
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
