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https://issues.apache.org/jira/browse/CASSANDRA-5239?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14380940#comment-14380940
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Benedict edited comment on CASSANDRA-5239 at 3/25/15 10:46 PM:
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bq. are you talking about something like streaming a large result set?
Right. But the definition of "large" is important. Really I'm talking about
ensuring all queries require a fixed number of resources (or thereabouts), and
that returning the entire result can be done without significant extra overhead
nor breaking isolation, so that even relatively modest resultsets can be
"streamed".
bq. doesn't seem like it's much better/worse
Exactly my point: as such it doesn't seem to be an intervening step, so using
it as one isn't a good justification for this patch. Either way, this is IMO
one of the more pressing concerns to address in the near future, and my view is
we should decide what our approximate end goal looks like concretely, and base
any intervening states on that.
was (Author: benedict):
bq. doesn't seem like it's much better/worse
Exactly my point: as such it doesn't seem to be an intervening step, so using
it as one isn't a good justification for this patch. Either way, this is IMO
one of the more pressing concerns to address in the near future, and my view is
we should decide what our approximate end goal looks like concretely, and base
any intervening states on that.
> Asynchronous (non-blocking) StorageProxy
> ----------------------------------------
>
> Key: CASSANDRA-5239
> URL: https://issues.apache.org/jira/browse/CASSANDRA-5239
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Affects Versions: 2.0 beta 1
> Reporter: Vijay
> Labels: performance
> Fix For: 3.0
>
>
> Problem Statement:
> Currently we have "rpc_min_threads, rpc_max_threads"/
> "native_transport_min_threads/native_transport_max_threads" all of the
> threads in the TPE are blocking and takes resources, the threads are mostly
> sleeping. Increasing the Context switch costs.
> Details:
> We should change StorageProxy methods to provide a callback which contains
> the location where the results has to be written. When the response arrive
> StorageProxy callback can write the results directly into the connection.
> Timeouts can be handled in the same way.
> Fixing Netty should be trivial with some refactor in the storage proxy
> (currently it is one method call for sending the request and waiting) we need
> callback.
> Fixing Thrift may be harder because thrift calls the method and expects a
> return value. We might need to write a custom Codec on Netty for thrift
> support, which can potentially do callbacks (A Custom codec may be similar to
> http://engineering.twitter.com/2011/04/twitter-search-is-now-3x-faster_1656.html
> but we dont know details about it). Another option is to update thrift to
> have a callback.
> FYI, The motivation for this ticket is from another project which i am
> working on with similar Proxy (blocking Netty transport) and making it Async
> gave us 2x throughput improvement.
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