[ZODB-Dev] [Plone-developers] ZODB on a DHT for P2P Plone

[Aran Dunkley]

Hi, after looking in to Plone/ZODB we've found that it will not be an
appropriate technology for P2P use.

Firstly Plone would need to be modified greatly to ensure that it works
in a way where it maintains indexes rather than performing real-time
queries due to the high latency and intermittent availability of peers.

>From the ZODB aspect the closest storage layer to working in P2P is NEO,
but Vincent from the NEO developer team pointed out that it won't be
ready for P2P for some time yet:
------------
> As one of the NEO team, what are your thoughts on the practicality of
> running Plone in a P2P environment with the latencies experienced in
> standard DHT (such as for example those based on Kademlia)
> implemtations?
First, I must say that we have not run any benchmark on NEO outside LAN
conditions yet, because there are some issues which need attention
before we can increase test hostility. To name a few blockers, there is
a need for "peaceful" deadlock resolution/avoidance when the same set of
objects gets modified concurrently, and an important "from scratch"
replication performance issue. Another show-stopper for NEO
production-readiness is the lack of backup tools, as NEO currently
relies on storage back-end tools (eg. mysqldump) and on a replication
scheme which is not implemented (useful in a all-nodes-in-datacenter
setup, not if nodes are to be scattered around the globe).
------------
On the bright side, we have found a technology which looks very
promising which is Squeak (open source Smalltalk) and the Seaside web
application framework, so we'll be pursuing this route more deeply for a
while. Thanks all for your advice and feedback :-)
Cheers,
Aran

On 08/01/11 05:04, Carol Ganz wrote:
> Hello Aran,
> 
> This project looks very interesting and we would be happy to enter into discussions with you on the feasibility of the proposed architecture. 
> 
> Six Feet Up excels in helping clients with complex requirements deliver easy-to-use products to their users. Our proven project management skills are invaluable to our partners through the cost savings they provide (http://www.sixfeetup.com/blog/how-to-save-40-percent-on-development-costs). Well-defined development processes, backed up by in-house quality assurance and Hudson testing, ensure the high quality of our code and that the results we produce are exceptional. Six Feet Up develops long-term partnerships with our clients through transparency in every step of the process and involving decision makers from day one.
> 
> Is your team to the point of entering into a discovery phase to define the project and to begin prototyping? I would like to schedule a meeting to discuss this project at your convenience.
> 
> Thank you,
> Carol Ganz
> Account Manager
>