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From Jonathan Haddad <...@jonhaddad.com>
Subject Re: [MASSMAIL]Re: Inconsistent behavior during read
Date Thu, 25 Jun 2015 16:06:22 GMT
Quorum will give you strong consistency, but if you're using RF=2 you're
going to have issues, as Quorum on RF=2 = CL=ALL.  You'll want to use RF=3
to make sure you can tolerate failure of a node, otherwise a single node
going down will result in unanswerable queries.

On Thu, Jun 25, 2015 at 6:37 AM Marcos Ortiz <mlortiz@uci.cu> wrote:

>  Regards, Aditya. I´m agree with Jack here. In our tests here with read
> and writes in Cassandra (version 2.1.5), we played with several CL, and
> QUORUM is the best for us.
>
>
> On 25/06/15 08:14, Jack Krupansky wrote:
>
> Hinted handoff - which is what provides eventual consistency - can time
> out and be discarded/lost if the cluster is under heavy load or encounters
> poor network connectivity or nodes are down for too long, which is what
> requires running repair. That's why quorum is the recommended cl for both
> write and read for true consistency.
>
>  -- Jack Krupansky
>
> On Thu, Jun 25, 2015 at 7:51 AM, Alain RODRIGUEZ <arodrime@gmail.com>
> wrote:
>
>> Excepted if the node failed to take the write and you have no Hinted
>> Handoff (or for some reason they also failed).
>>
>>  Have you tried at QUORUM or even ALL, this would force a synchronous
>> read repair. You can also try to repair directly.
>>
>>  Hope this will help,
>>
>>  C*heers,
>>
>>  Alain
>>
>> 2015-06-25 13:34 GMT+02:00 Aditya Shetty <aditya.shetty@snapdeal.com>:
>>
>>> I am using consistency one for both. However, the writes had happened a
>>> few days before, so it does not look like an issue of eventual consistency.
>>>
>>> On Thu, Jun 25, 2015 at 3:59 PM, Perica Milošević <
>>> perica.milosevic@gmail.com> wrote:
>>>
>>>> Which ConsistencyLevel do you use for writing and reading of the data?
>>>>
>>>>  Cheers,
>>>> Perica
>>>>
>>>>
>>>> On Thu, Jun 25, 2015 at 12:12 PM, Aditya Shetty <
>>>> aditya.shetty@snapdeal.com> wrote:
>>>>
>>>>>  Hi
>>>>>
>>>>>  I have a 3 node cassandra cluster with a replication factor of 2. I
>>>>> have a basic column family which I am reading by primary key. Here is
the
>>>>> CF structure:
>>>>>
>>>>> CREATE TABLE reviews_platform.object_stats (
>>>>>
>>>>>     object_owner_id int,
>>>>>
>>>>>     object_type int,
>>>>>
>>>>>     object_id text,
>>>>>     num_of_reviews int,    PRIMARY KEY ((object_owner_id,
>>>>> object_type), object_id)
>>>>>
>>>>> );
>>>>> However, when I query this column family by primary key, I sometimes
>>>>> get no records, even though the record exists. The same query after some
>>>>> time gives a proper response.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> *Query: select * from reviews_platform.object_stats where object_id =
>>>>> '674813358269' and object_type = 0 and object_owner_id = 0; *
>>>>>  Note that I am querying using the java driver.
>>>>>
>>>>> --
>>>>>
>>>>>  Aditya Shetty
>>>>> *Lead Engineer*
>>>>>
>>>>>  *M*: +91 7022423545, *T*: 080 46603000 *EXT*: 4417
>>>>>  2nd FLOOR, WEST WING,
>>>>>
>>>>> SALARPURIA SUPREME, MARATHAHALLI, BENGALURU
>>>>>
>>>>>      Download Our App    [image: A]
>>>>> <https://play.google.com/store/apps/details?id=com.snapdeal.main&utm_source=mobileAppLp&utm_campaign=android>
>>>>>  [image: A]
>>>>> <https://itunes.apple.com/in/app/snapdeal-mobile-shopping/id721124909?ls=1&mt=8&utm_source=mobileAppLp&utm_campaign=ios>
>>>>>  [image: W]
>>>>> <http://www.windowsphone.com/en-in/store/app/snapdeal/ee17fccf-40d0-4a59-80a3-04da47a5553f>
>>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>>
>>>  Aditya Shetty
>>> *Lead Engineer*
>>>
>>>  *M*: +91 7022423545 <%2B91%207022423545>, *T*: 080 46603000 *EXT*: 4417
>>>  2nd FLOOR, WEST WING,
>>>
>>> SALARPURIA SUPREME, MARATHAHALLI, BENGALURU
>>>
>>>      Download Our App    [image: A]
>>> <https://play.google.com/store/apps/details?id=com.snapdeal.main&utm_source=mobileAppLp&utm_campaign=android>
>>>  [image: A]
>>> <https://itunes.apple.com/in/app/snapdeal-mobile-shopping/id721124909?ls=1&mt=8&utm_source=mobileAppLp&utm_campaign=ios>
>>>  [image: W]
>>> <http://www.windowsphone.com/en-in/store/app/snapdeal/ee17fccf-40d0-4a59-80a3-04da47a5553f>
>>>
>>
>>
>
> --
> Marcos Ortiz <http://about.me/marcosortiz>, Sr. Product Manager (Data
> Infrastructure) at UCI
> @marcosluis2186 <http://twitter.com/marcosluis2186>
>
>
>

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