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From "Laing, Michael" <michael.la...@nytimes.com>
Subject Re: Question about consistency
Date Wed, 09 Sep 2015 15:16:40 GMT
"alter table test.test_root WITH speculative_retry = '0.0PERCENTILE';"

seemed to work for me with C* version 2.1.7

On Wed, Sep 9, 2015 at 10:11 AM, Eric Plowe <eric.plowe@gmail.com> wrote:

> Would this work:
>
> ALTER TABLE session_state WITH speculative_retry = '0ms';
> ALTER TABLE session_state WITH speculative_retry = '0PERCENTILE';
>
> I can't set it to 0, but was wondering if these would have the same
> effect?
>
> ~Eric
>
> On Wed, Sep 9, 2015 at 8:19 AM, Eric Plowe <eric.plowe@gmail.com> wrote:
>
>> Interesting. I'll give it a try and report back my findings.
>>
>> Thank you, Michael.
>>
>>
>> On Wednesday, September 9, 2015, Laing, Michael <
>> michael.laing@nytimes.com> wrote:
>>
>>> Perhaps a variation on
>>> https://issues.apache.org/jira/browse/CASSANDRA-9753?
>>>
>>> You could try setting speculative retry to 0 to avoid cross-dc reads.
>>>
>>> On Wed, Sep 9, 2015 at 7:55 AM, Eric Plowe <eric.plowe@gmail.com> wrote:
>>>
>>>> read_repair_chance: 0
>>>> dclocal_read_repair_chance: 0.1
>>>>
>>>>
>>>> On Wednesday, September 9, 2015, Laing, Michael <
>>>> michael.laing@nytimes.com> wrote:
>>>>
>>>>> What are your read repair settings?
>>>>>
>>>>> On Tue, Sep 8, 2015 at 9:28 PM, Eric Plowe <eric.plowe@gmail.com>
>>>>> wrote:
>>>>>
>>>>>> To further expand. We have two data centers, Miami and Dallas. Dallas
>>>>>> is our disaster recovery data center. The cluster has 12 nodes, 6
in Miami
>>>>>> and 6 in Dallas. The servers in Miami only read/write to Miami using
data
>>>>>> center aware load balancing policy of the driver. We have the problem
when
>>>>>> writing and reading to the Miami cluster with LOCAL_QUORUM.
>>>>>>
>>>>>> Regards,
>>>>>>
>>>>>> Eric
>>>>>>
>>>>>> On Tuesday, September 8, 2015, Eric Plowe <eric.plowe@gmail.com>
>>>>>> wrote:
>>>>>>
>>>>>>> Rob,
>>>>>>>
>>>>>>> All writes/reads are happening from DC1. DC2 is a backup. The
web
>>>>>>> app does not handle live requests from DC2.
>>>>>>>
>>>>>>> Regards,
>>>>>>>
>>>>>>> Eric Plowe
>>>>>>>
>>>>>>> On Tuesday, September 8, 2015, Robert Coli <rcoli@eventbrite.com>
>>>>>>> wrote:
>>>>>>>
>>>>>>>> On Tue, Sep 8, 2015 at 4:40 PM, Eric Plowe <eric.plowe@gmail.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> I'm using Cassandra as a storage mechanism for session
state
>>>>>>>>> persistence for an ASP.NET web application. I am seeing
issues
>>>>>>>>> where the session state is persisted on one page (setting
a value:
>>>>>>>>> Session["key"] = "value" and when it redirects to another
(from a post back
>>>>>>>>> event) and check for the existence of the value that
was set, it doesn't
>>>>>>>>> exist.
>>>>>>>>>
>>>>>>>>> It's a 12 node cluster with 2 data centers (6 and 6)
running
>>>>>>>>> 2.1.9. The key space that the column family lives has
a RF of 3
>>>>>>>>> for each data center. The session state provider is using
the the datastax
>>>>>>>>> csharp driver v2.1.6. Writes and reads are at LOCAL_QUORUM.
>>>>>>>>>
>>>>>>>>
>>>>>>>> 1) Write to DC_A with LOCAL_QUORUM
>>>>>>>> 2) Replication to DC_B takes longer than it takes to...
>>>>>>>> 3) Read from DC_B with LOCAL_QUORUM, do not see the write
from 1)
>>>>>>>>
>>>>>>>> If you want to be able to read your writes from DC_A in DC_B,
>>>>>>>> you're going to need to use EACH_QUORUM.
>>>>>>>>
>>>>>>>> =Rob
>>>>>>>>
>>>>>>>>
>>>>>
>>>
>

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