[OSGeo-Discuss] RE: OGC WPS and Amazon SQS

[Dr. Markus Lupp]

Hi Randy,

deegree has a WPS implementation (although by now it supports only WPS 
v. 0.4.0). We plan to publish an easy-to-install WPS Demo Release for 
deegree 2.2, coming in June (1st Release Candidate in April).


Regards,

Markus



Randy George schrieb:
>
> I noticed OGC finalized the WPS spec: 
> http://www.opengeospatial.org/pressroom/pressreleases/843
>
> Does anyone know of projects working on WPS implementations?
>
> The goal of WPS is apparently to provide a consistent framework for 
> interchangeable service process algorithms that can potentially be 
> chained together into answers to higher level questions than the 
> typical ‘what’, ‘when’, and ‘where.’ Dealing with ‘why’, ‘how much’, 
> and ‘what if’ modeling usually requires a process pipeline for 
> convolutions, boolean band operations, and summary pixel calculations, 
> all of which are cpu cycle intense, especially for large imagery sets. 
> In fact cpu usage issues would make the usual service approach 
> prohibitive. Even the little I have worked on JAI pipelines shows me 
> the futility of a one cpu to many service requests approach for WPS.
>
> However, looking at the AWS Simple Queue Service, SQS 
> http://www.amazon.com/Simple-Queue-Service-home-page/b/ref=sc_fe_l_2?ie=UTF8&node=13584001&no=3435361&me=A36L942TSJ2AJA 
> <http://www.amazon.com/Simple-Queue-Service-home-page/b/ref=sc_fe_l_2?ie=UTF8&node=13584001&no=3435361&me=A36L942TSJ2AJA>, 
> some interesting possibilities come to mind.
>
> Locking message queues with AMI instance pools is essentially a poor 
> man’s supercomputer. It would be interesting to look at harnessing the 
> utility computing concept with instance pools available for each stage 
> in a process pipeline connected using the asynchronous SQS service. 
> This is a more or less controlled ‘distributed computing model’ 
> applied to WPS.
>
> Ref here for some examples of existing distributed computing projects: 
> http://distributedcomputing.info/projects.html
>
> Here are a couple possible approaches to a WPS service model that 
> might overcome the cpu bottle neck:
>
> 1) Sequential SQS pipeline with dedicated instance for each process 
> node - this would work best for operations amenable to a streaming 
> pipeline – Boolean band operations or pixel summary operations for 
> instance
>
> 2) Distributed computing model with a chunk server feeding a pipeline 
> and an array pool of instances processing the chunks coming down the 
> SQS queue – this would be better suited to tiled operations
>
> WPS is great when someone else provides the service. I imagine it 
> would be very interesting to the academic scientific world and 
> government groups tasked with providing access to all the myriad 
> imagery coming off space sensor platforms.
>
> Just thinking out loud. More thoughts here: 
> http://www.cadmaps.com/gisblog/?p=28
>
> randy
>
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-- 
Dr. Markus Lupp
l a t / l o n  GmbH
Kupang-NTT
Indonesia
phone +62 (0)81 339 431666
http://www.lat-lon.de
http://www.deegree.org
--