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From Voytek Jarnot <voytek.jar...@gmail.com>
Subject Re: Very odd & inconsistent results from SASI query
Date Mon, 20 Mar 2017 20:11:13 GMT
Appreciate the reply, Kurt.

I sanitized it out of the traces, but all trace outputs listed the same
node for all three queries (1 working, 2 not working). Read repair chance
set to 0.0 as recommended when using TWCS.

I'll check tpstats - in this environment, load is not an issue, but network
issues may be.

On Mon, Mar 20, 2017 at 2:42 PM, kurt greaves <kurt@instaclustr.com> wrote:

> As secondary indexes are stored individually on each node what you're
> suggesting sounds exactly like a consistency issue. the fact that you read
> 0 cells on one query implies the node that got the query did not have any
> data for the row. The reason you would sometimes see different behaviours
> is likely because of read repairs. The fact that the repair guides the
> issue pretty much guarantees it's a consistency issue.
>
> You should check for dropped mutations in tpstats/logs and if they are
> occurring try and stop that from happening (probably load related). You
> could also try performing reads and writes at LOCAL_QUORUM for stronger
> consistency, however note this has a performance/latency impact.
>
>
>

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