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Date: Thu, 16 Jun 2011 10:10:08 -0700
Message-ID: <BANLkTik5dSP7j4g2X3S=D_hzywsHrraEqw@mail.gmail.com>
Subject: Re: Propose new ConsistencyLevel.ALL_AVAIL for reads
From: Yang <teddyyyy123@gmail.com>
To: user@cassandra.apache.org
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consistency level definition should be a definition of requirement from the
application perspective,
it should not be tied to some ephemeral state in the system (: a node being
deemed "available/up" or down is determined by
the gossip and changes every second )


what you want can be simply achieved by CL=ALL and then modifying current
read result to not return failure, but return the "best effort" result
obtained so far
--- although that will need you to wait for a slightly longer time


On Thu, Jun 16, 2011 at 9:46 AM, AJ <aj@dude.podzone.net> wrote:

> On 6/16/2011 10:05 AM, Ryan King wrote:
>
>>
>> I don't think this buys you anything that you can't get with quorum
>> reads and writes.
>>
>> -ryan
>>
>>
> QUORUM <= ALL_AVAIL <= ALL == RF
>

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consistency level definition should be a definition of requirement from the=
 application perspective,<div>it should not be tied to some ephemeral state=
 in the system (: a node being deemed &quot;available/up&quot; or down is d=
etermined by=A0</div>
<div>the gossip and changes every second )</div><div><br></div><div><br></d=
iv><div>what you want can be simply achieved by CL=3DALL and then modifying=
 current read result to not return failure, but return the &quot;best effor=
t&quot; result obtained so far</div>
<div>--- although that will need you to wait for a slightly longer time</di=
v><div><br></div><div><br></div><div><br><br><div class=3D"gmail_quote">On =
Thu, Jun 16, 2011 at 9:46 AM, AJ <span dir=3D"ltr">&lt;<a href=3D"mailto:aj=
@dude.podzone.net" target=3D"_blank">aj@dude.podzone.net</a>&gt;</span> wro=
te:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
<div>On 6/16/2011 10:05 AM, Ryan King wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
<br>
I don&#39;t think this buys you anything that you can&#39;t get with quorum=
<br>
reads and writes.<br>
<br>
-ryan<br>
<br>
</blockquote>
<br></div>
QUORUM &lt;=3D ALL_AVAIL &lt;=3D ALL =3D=3D RF<br>
</blockquote></div><br>
</div>

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