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From Apoorva Gaurav <apoorva.gau...@myntra.com>
Subject Re: Read performance in map data type
Date Wed, 02 Apr 2014 06:12:11 GMT
I've observed that reducing fetch size results in better latency (isn't
that obvious :-)), tried from fetch size varying from 100 to 10000, seeing
a lot of errors for 10000. Haven't tried modifying the number of columns.

Let me start a new thread focused on fetch size.


On Wed, Apr 2, 2014 at 9:53 AM, Sourabh Agrawal <iitr.sourabh@gmail.com>wrote:

> From the doc : The fetch size controls how much resulting rows will be
> retrieved simultaneously.
> So, I guess it does not depend on the number of columns as such. As all
> the columns for a key reside on the same node, I think it wouldn't matter
> much whatever be the number of columns as long as we have enough memory in
> the app.
>
> Default value is 5000. (com.datastax.driver.core.QueryOptions)
>
> We use it with the default value. I have never profiled cassandra for read
> load. If you profile it for different fetch sizes, please share the results
> :)
>
>
> On Wed, Apr 2, 2014 at 8:45 AM, Apoorva Gaurav <apoorva.gaurav@myntra.com>wrote:
>
>> Thanks Sourabh,
>>
>> I've modelled my table as "studentID int, subjectID int, marks int,
>> PRIMARY KEY(studentID, subjectID)" as primarily I'll be querying using
>> studentID and sometime using studentID and subjectID.
>>
>> I've tried driver 2.0.0 and its giving good results. Also using its auto
>> paging feature. Any idea what should be a typical value for fetch size. And
>> does the fetch size depends on how many columns are there in the CQL table
>> for e.g. should fetch size in a table like "studentID int, subjectID
>> int, marks1 int, marks2 int, marks3 int.... marksN int PRIMARY
>> KEY(studentID, subjectID)" be less than fetch size in "studentID int,
>> subjectID int, marks int, PRIMARY KEY(studentID, subjectID)"
>>
>>
>> On Wed, Apr 2, 2014 at 2:20 AM, Robert Coli <rcoli@eventbrite.com> wrote:
>>
>>>  On Mon, Mar 31, 2014 at 9:13 PM, Apoorva Gaurav <
>>> apoorva.gaurav@myntra.com> wrote:
>>>
>>>> Thanks Robert, Is there a workaround, as in our test setups we keep
>>>> dropping and recreating tables.
>>>>
>>>
>>> Use unique keyspace (or table) names for each test? That's the approach
>>> they're taking in 5202...
>>>
>>> =Rob
>>>
>>>
>>
>>
>> --
>> Thanks & Regards,
>> Apoorva
>>
>
>
>
> --
> Sourabh Agrawal
> Bangalore
> +91 9945657973
>



-- 
Thanks & Regards,
Apoorva

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