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From Watanabe Maki <watanabe.m...@gmail.com>
Subject Re: 1.1.1 is "repair" still needed ?
Date Fri, 12 Oct 2012 00:23:36 GMT
Oh sorry. It's pretty nice to know that.


On 2012/10/12, at 0:18, "B. Todd Burruss" <btoddb@gmail.com> wrote:

> as of 1.0 (CASSANDRA-2034) hints are generated for nodes that timeout.
> 
> On Thu, Oct 11, 2012 at 3:55 AM, Watanabe Maki <watanabe.maki@gmail.com> wrote:
>> Even if HH works fine, HH will not be created until the failure detector marks  the
node is dead.
>> HH will not be created for partially timeouted mutation request ( but meets CL )
also... In my understanding...
>> 
>> 
>> On 2012/10/11, at 5:55, Rob Coli <rcoli@palominodb.com> wrote:
>> 
>>> On Tue, Oct 9, 2012 at 12:56 PM, Oleg Dulin <oleg.dulin@gmail.com> wrote:
>>>> My understanding is that the repair has to happen within gc_grace period.
>>>> [ snip ]
>>>> So the question is, is this still needed ? Do we even need to run nodetool
>>>> repair ?
>>> 
>>> If Hinted Handoff works in your version of Cassandra, and that version
>>> is > 1.0, you "should" not need to repair if no node has crashed or
>>> been down for longer than max_hint_window_in_ms. This is because after
>>> 1.0, any failed write to a remote replica results in a hint, so any
>>> DELETE should eventually be fully replicated.
>>> 
>>> However hinted handoff is meaningfully broken between 1.1.0 and 1.1.6
>>> (unreleased) so you cannot rely on the above heuristic for
>>> consistency. In these versions, you have to repair (or read repair
>>> 100% of keys) once every GCGraceSeconds to prevent the possibility of
>>> zombie data. If it were possible to repair on a per-columnfamily
>>> basis, you could get a significant win by only repairing
>>> columnfamilies which take DELETE traffic.
>>> 
>>> https://issues.apache.org/jira/browse/CASSANDRA-4772
>>> 
>>> =Rob
>>> 
>>> --
>>> =Robert Coli
>>> AIM&GTALK - rcoli@palominodb.com
>>> YAHOO - rcoli.palominob
>>> SKYPE - rcoli_palominodb

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