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From Shahab Yunus <shahab.yu...@gmail.com>
Subject Re: Dropped mutation messages
Date Wed, 19 Jun 2013 12:40:34 GMT
Hello Arthur,

What do you mean by "The queries need to be lightened"?

Thanks,
Shahb


On Tue, Jun 18, 2013 at 8:47 PM, Arthur Zubarev <Arthur.Zubarev@aol.com>wrote:

>   Cem hi,
>
> as per http://wiki.apache.org/cassandra/FAQ#dropped_messages
>
>
> Internode messages which are received by a node, but do not get not to be
> processed within rpc_timeout are dropped rather than processed. As the
> coordinator node will no longer be waiting for a response. If the
> Coordinator node does not receive Consistency Level responses before the
> rpc_timeout it will return a TimedOutException to the client. If the
> coordinator receives Consistency Level responses it will return success to
> the client.
>
> For MUTATION messages this means that the mutation was not applied to all
> replicas it was sent to. The inconsistency will be repaired by Read Repair
> or Anti Entropy Repair.
>
> For READ messages this means a read request may not have completed.
>
> Load shedding is part of the Cassandra architecture, if this is a
> persistent issue it is generally a sign of an overloaded node or cluster.
>
> By the way, I am on C* 1.2.4 too in dev mode, after having my node filled
> with 400 GB I started getting RPC timeouts on large data retrievals, so in
> short, you may need to revise how you query.
>
> The queries need to be lightened
>
> /Arthur
>
>  *From:* cem <cayiroglu@gmail.com>
> *Sent:* Tuesday, June 18, 2013 1:12 PM
> *To:* user@cassandra.apache.org
> *Subject:* Dropped mutation messages
>
>  Hi All,
>
> I have a cluster of 5 nodes with C* 1.2.4.
>
> Each node has 4 disks 1 TB each.
>
> I see  a lot of dropped messages after it stores 400 GB  per disk. (1.6 TB
> per node).
>
> The recommendation was 500 GB max per node before 1.2.  Datastax says that
> we can store terabytes of data per node with 1.2.
> http://www.datastax.com/docs/1.2/cluster_architecture/cluster_planning
>
> Do I need to enable anything to leverage from 1.2? Do you have any other
> advice?
>
> What should be the path to investigate this?
>
> Thanks in advance!
>
> Best Regards,
> Cem.
>
>
>

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