cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Benedict (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-8483) Support streaming results
Date Mon, 15 Dec 2014 14:46:13 GMT


Benedict commented on CASSANDRA-8483:

Isolation over a given partition; isolation across partitions isn't ever offered.

If you want isolation over a large partition you pay the cost of preventing reclamation of
expired sstables until the read completes, but that is all. If you expect the partition to
be so large that's a problem, you're probably doing it wrong, but can always fall back to

> Support streaming results
> -------------------------
>                 Key: CASSANDRA-8483
>                 URL:
>             Project: Cassandra
>          Issue Type: Sub-task
>          Components: Core
>            Reporter: Benedict
>             Fix For: 3.0
> Currently we stream the number of rows back to the client before serializing, which means
we need to know how many there are before doing so, which means materializing the entire resultset.
We currently get around this with paging which attempts to restrict the amount of materialization
done in any step, but supporting streaming entire result sets in one native transport "action"
without materializing them all upfront would remove the need for paging in many cases, and
would permit resultsets to be streamed _with isolation_, which most users probably don't realise
is broken by paging.
> We can't use this change yet, but the sooner support for this is introduced to the protocol,
the more likely it is clients will be able to make use of streaming reads once we're actually
able to deliver them.

This message was sent by Atlassian JIRA

View raw message