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From sankalp kohli <kohlisank...@gmail.com>
Subject Re: Read during digest mismatch
Date Wed, 14 Nov 2012 03:14:37 GMT
Thats correct


On Tue, Nov 13, 2012 at 7:06 PM, Wz1975 <wz1975@yahoo.com> wrote:

> From my understanding,  if CL = 2, one read,  one digest are sent.  Only
> if it is    read repair,  digest is sent to all replicates.
>
>
> Thanks.
> -Wei
>
> Sent from my Samsung smartphone on AT&T
>
>
> -------- Original message --------
> Subject: Re: Read during digest mismatch
> From: Edward Capriolo <edlinuxguru@gmail.com>
> To: "user@cassandra.apache.org" <user@cassandra.apache.org>
> CC:
>
>
> I think the code base does not benefit from having too many different read
> code paths. Logically what your suggesting is reasonable, but you have to
> consider the case of one being slow to respond.
>
> Then what?
>
> On Tuesday, November 13, 2012, Manu Zhang <owenzhang1990@gmail.com> wrote:
> > If consistency is two, don't we just send data request to one and digest
> request to another?
> >
> > On Mon, Nov 12, 2012 at 2:49 AM, Jonathan Ellis <jbellis@gmail.com>
> wrote:
> >>
> >> Correct.  Which is one reason there is a separate setting for
> >> cross-datacenter read repair, by the way.
> >>
> >> On Thu, Nov 8, 2012 at 4:43 PM, sankalp kohli <kohlisankalp@gmail.com>
> wrote:
> >> > Hi,
> >> >     Lets say I am reading with consistency TWO and my replication is
> 3. The
> >> > read is eligible for global read repair. It will send a request to
> get data
> >> > from one node and a digest request to two.
> >> > If there is a digest mismatch, what I am reading from the code looks
> like it
> >> > will get the data from all three nodes and do a resolve of the data
> before
> >> > returning to the client.
> >> >
> >> > Is it correct or I am readind the code wrong?
> >> >
> >> > Also if this is correct, look like if the third node is in other DC,
> the
> >> > read will slow down even when the consistency was TWO?
> >> >
> >> > Thanks,
> >> > Sankalp
> >> >
> >> >
> >>
> >>
> >>
> >> --
> >> Jonathan Ellis
> >> Project Chair, Apache Cassandra
> >> co-founder of DataStax, the source for professional Cassandra support
> >> http://www.datastax.com
> >
> >
>

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