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From Brian Tarbox <tar...@cabotresearch.com>
Subject Re: in AWS is it worth trying to talk to a server in the same zone as your client?
Date Wed, 12 Feb 2014 21:29:30 GMT
We're definitely using all private IPs.

I guess my question really is: with repl=3 and quorum operations I know
we're going to push/pull bits across the various AZs within us-east-1.  So,
does having the client start the conversation with a server in the same AZ
save us anything?


On Wed, Feb 12, 2014 at 4:14 PM, Ben Bromhead <ben@instaclustr.com> wrote:

> 0.01/G between zones irrespective of IP is correct.
>
> As for your original question, depending on the driver you are using you
> could write a custom co-ordinator node selection policy.
>
> For example if you are using the Datastax driver you would extend
> http://www.datastax.com/drivers/java/2.0/apidocs/com/datastax/driver/core/policies/LoadBalancingPolicy.html
>
> ... and set the distance based on which zone the node is in.
>
> An alternate method would be to define the zones as data centres and then
> you could leverage existing DC aware policies (We've never tried this
> though).
>
>
> Ben Bromhead
> Instaclustr | www.instaclustr.com | @instaclustr<http://twitter.com/instaclustr>
|
> +61 415 936 359
>
>
>
>
> On 13/02/2014, at 8:00 AM, Andrey Ilinykh <ailinykh@gmail.com> wrote:
>
> I think you are mistaken. It is true for the same zone. between zones
> 0.01/G
>
>
> On Wed, Feb 12, 2014 at 12:17 PM, Russell Bradberry <rbradberry@gmail.com>wrote:
>
>> Not when using private IP addresses.  That pricing *ONLY *applies if you
>> are using the public interface or EIP/ENI.  If you use the private IP
>> addresses there is no cost associated.
>>
>>
>>
>> On February 12, 2014 at 3:13:58 PM, William Oberman (
>> oberman@civicscience.com <//oberman@civicscience.com>) wrote:
>>
>> Same region, cross zone transfer is $0.01 / GB (see
>> http://aws.amazon.com/ec2/pricing/, Data Transfer section).
>>
>>
>> On Wed, Feb 12, 2014 at 3:04 PM, Russell Bradberry <rbradberry@gmail.com>wrote:
>>
>>>  Cross zone data transfer does not cost any extra money.
>>>
>>>  LOCAL_QUORUM = QUORUM if all 6 servers are located in the same logical
>>> datacenter.
>>>
>>>  Ensure your clients are connecting to either the local IP or the AWS
>>> hostname that is a CNAME to the local ip from within AWS.  If you connect
>>> to the public IP you will get charged for outbound data transfer.
>>>
>>>
>>>
>>> On February 12, 2014 at 2:58:07 PM, Yogi Nerella (ynerella999@gmail.com<//ynerella999@gmail.com>)
>>> wrote:
>>>
>>>  Also, may be you need to check the read consistency to local_quorum,
>>> otherwise the servers still try to read the data from all other data
>>> centers.
>>>
>>> I can understand the latency, but I cant understand how it would save
>>> money?   The amount of data transferred from the AWS server to the client
>>> should be same no matter where the client is connected?
>>>
>>>
>>>
>>> On Wed, Feb 12, 2014 at 10:33 AM, Andrey Ilinykh <ailinykh@gmail.com>wrote:
>>>
>>>> yes, sure. Taking data from the same zone will reduce latency and save
>>>> you some money.
>>>>
>>>>
>>>> On Wed, Feb 12, 2014 at 10:13 AM, Brian Tarbox <
>>>> tarbox@cabotresearch.com> wrote:
>>>>
>>>>> We're running a C* cluster with 6 servers spread across the four
>>>>> us-east1 zones.
>>>>>
>>>>> We also spread our clients (hundreds of them) across the four zones.
>>>>>
>>>>> Currently we give our clients a connection string listing all six
>>>>> servers and let C* do its thing.
>>>>>
>>>>> This is all working just fine...and we're paying a fair bit in AWS
>>>>> transfer costs.  There is a suspicion that this transfer cost is driven
by
>>>>> us passing data around between our C* servers and clients.
>>>>>
>>>>> Would there be any value to trying to get a client to talk to one of
>>>>> the C* servers in its own zone?
>>>>>
>>>>> I understand (at least partially!) about coordinator nodes and
>>>>> replication and know that no matter which server is the coordinator for
an
>>>>> operation replication may cause bits to get transferred to/from servers
in
>>>>> other zones.  Having said that...is there a chance that trying to encourage
>>>>> a client to initially contact a server in its own zone would help?
>>>>>
>>>>> Thank you,
>>>>>
>>>>> Brian Tarbox
>>>>>
>>>>>
>>>>
>>>
>>
>>
>>
>>
>
>

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