cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Aleksey Yeschenko (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (CASSANDRA-11980) Reads at EACH_QUORUM not respecting the level with read repair or speculative retry active
Date Wed, 08 Jun 2016 16:01:21 GMT

     [ https://issues.apache.org/jira/browse/CASSANDRA-11980?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Aleksey Yeschenko updated CASSANDRA-11980:
------------------------------------------
    Since Version: 3.0.0 rc2

> Reads at EACH_QUORUM not respecting the level with read repair or speculative retry active
> ------------------------------------------------------------------------------------------
>
>                 Key: CASSANDRA-11980
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11980
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Coordination
>            Reporter: Aleksey Yeschenko
>
> {{ReadCallback::waitingFor()}} is not sophisticated enough to correctly count replies
from replicas towards {{blockFor}}, and can return to the client before getting an actual
quorum in each of the DCs.
> Assume DC1: n1, n2, n3; DC2: n4, n5, n6; blockFor in this case would be 4. {{ReadCallback}}
does not count replies from different DCs separately, however, so if the replies return in
order of n1, n2, n3, n4, the request will still succeed, having achieved 4, despite not getting
a quorum from DC2.
> The bug potentially manifests itself if RR.GLOBAL, RR.LOCAL, or any speculative retry
triggers.
> The easiest fix would be to temporarily disable RR and speculative retry on each quorum
reads.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message