incubator-s4-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From benner <gothi...@gmx.de>
Subject Re: Question about dynamic application deployment
Date Mon, 07 Jan 2013 07:13:57 GMT
Hi Matthieu,

thanks for you answers, they helped me a lot.

Regards,
Benjamin

On 01/03/2013 04:16 PM, Matthieu Morel wrote:
> Hi Benjamin, some answers inline:
>
> On Jan 3, 2013, at 15:55 , Benjamin Süß wrote:
>>
>> in the overview about s4 v0.5 I there is a point mentioning "dynamic 
>> application deployment". Unfortunately I could not find any further 
>> information about this so I have some questions:
>>
>> 1.) In general, does this mean new applications can be added at 
>> cluster runtime?
>
> We cannot have multiple S4 applications on the same logical cluster. 
> But we can start with "empty" nodes and dynamically deploy an 
> application. This model facilitates porting the platform to other 
> infrastructures (e.g. Yarn), while keeping a common deployment scheme .
>
>>
>> 2.) If so, how about updating existing applications
>
> Currently we have to restart the nodes, and update the app reference 
> in Zookeeper. (The existing classloading machinery (inspired from 
> Hadoop's) could probably be extended to support automatic updating 
> though).
>
>>
>> 3.) If it is possible to update existing applications, what about 
>> data loss during updates?
>
> You can recover previous state through checkpointing and recovery, but 
> pending messages are lost.
>
>
> Hope this helps,
>
> Matthieu
>


Mime
View raw message