Emanuele wrote:
> Application is not supposed to be message-intensive: nodes perform
> local computation and than send aggregate date to some other node in
> the cluster.
> Anyway another concern to investigate regards the traffic weight
> generated by multiple clusters in a subnet (heartbeat message, leader
> election etc. etc.)
How many clusters are we talking about here? In our QE testing
environment at any given time we have at least 10 - 20 clusters testing
the GlassFish or Sailfin appserver which contains Shoal as clustering
engine. We have not seen any major issues with this.
The heartbeat message is sent once every period (configurable -
defaulted to 2 seconds) by each member using UDP.
Leader election is a discovery process at startup after which it is
deterministic so there is no network intensive leader election protocol
during the lifetime of the cluster except at startup.
>
> Emanuele
>
> Shreedhar Ganapathy ha scritto:
>>
>>
>> Emanuele wrote:
>>> Certainly. This could be a solution. But the challenge is to have a
>>> total decentralized system and a lus or a registry introduce a
>>> certain degree of centralization.
>>> I'm having a look at Shoal's code and JXTA api to understand how
>>> world group can be used for the purpose.
>>> Multicast port used by Shoal is fixed or changes from group to group?
>> The address and port should ideally be different from group to group
>> so that traffic in one group is not contaminating other groups. This
>> is essential for group view changes for each lifecycle event such as
>> a failure or a member join within a group and also for app level
>> messages.
>>
>> BTW, what are your needs with respect to messaging throughput.
>>>
>>> Emanuele
>>>
>>> Shreedhar Ganapathy wrote:
>>>> One could think of a registry or a lookup service a la Jini or a
>>>> UDDI registry or a JMX based MBean that exposes an API for
>>>> retrieving a collection of such Shoal groups. At the simplest level
>>>> these could just be a list of group names. But the important part
>>>> is the protocol for group discovery.
>>>>
>>>> Shreedhar Ganapathy wrote:
>>>>> Yes, we can expose a GMS API that will allow for a Uber entity for
>>>>> viewing a collection of groups. Jxta has traditionally had the
>>>>> advantage of being able to expose a compositional pattern of
>>>>> peergroups whereby a WorldPeerGroup composes of one or more
>>>>> infrastructure netpeergroups.
>>>>> I am hoping this can be done through Jxta. I am not sure if Mo is
>>>>> suggesting that GMS have a separate process of discovering all
>>>>> groups in a subnet. That would be a lot of design and development
>>>>> work in the GMS layer.
>>>>>
>>>>> Emanuele wrote:
>>>>>> My application is addressed to highly dynamic and fully
>>>>>> decentralized environments which impose a decentralized discovery
>>>>>> mechanism. Moreover I think such a feature could be essential to
>>>>>> enable self-organizing capabilities in these settings.
>>>>>>
>>>>>> Emanuele
>>>>>>
>>>>>> Mohamed Abdelaziz wrote:
>>>>>>>
>>>>>>>
>>>>>>> I think the simplest way is to expose a GMS API which allows for
>>>>>>> discovery of active clusters, which should be easy in the case
>>>>>>> of local sub-nets. It's a little tricky when crossing the
>>>>>>> sub-net boundries, which can be overcome by distributed queries
>>>>>>> cross networks, thus enabling such in geographically distributed
>>>>>>> clusters. Do you see a need for such feature in your application?
>>>>>>>
>>>>>>> Mohamed
>>>>>>>
>>>>>>> On Feb 15, 2008, at 5:07 PM, Emanuele <mane81_at_email.it> wrote:
>>>>>>>
>>>>>>>> Yes, something like that.
>>>>>>>> I'll try to be more precise with an example: suppose there is a
>>>>>>>> set of cluster in the system and clusters can be added and
>>>>>>>> removed at runtime. Entities belonging to one cluster can move
>>>>>>>> to another cluster according to some policies or rules. To
>>>>>>>> support this sort of dynamism a way to find current active
>>>>>>>> cluster is necessary.
>>>>>>>>
>>>>>>>> I think that I have to go deeper into JXTA api, but I would
>>>>>>>> appreciate any useful hints because I'm really new to Jxta :)
>>>>>>>>
>>>>>>>> Emanuele
>>>>>>>>
>>>>>>>> Shreedhar Ganapathy wrote:
>>>>>>>>> Does Jxta expose any api to query the world peer group for a
>>>>>>>>> specific infrastructure netpeergroup by name ?
>>>>>>>>>
>>>>>>>>> I think something of that kind is what Emanuele is asking for.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Mohamed Abdelaziz wrote:
>>>>>>>>>> Provided the cluster mcast port is known, discovery in world
>>>>>>>>>> group could be employed to discover cluster instances, a
>>>>>>>>>> functionality which could be exposed in shoal.
>>>>>>>>>>
>>>>>>>>>> Mohamed
>>>>>>>>>>
>>>>>>>>>> On Feb 15, 2008, at 2:14 PM, Shreedhar Ganapathy
>>>>>>>>>> <Shreedhar.Ganapathy_at_Sun.COM> wrote:
>>>>>>>>>>
>>>>>>>>>>> I am sure Jxta has some way to determine that. We probably
>>>>>>>>>>> dont know of it and hence Shoal Apis dont expose it. Would
>>>>>>>>>>> wait for Mohamed's response on this.
>>>>>>>>>>>
>>>>>>>>>>> Emanuele wrote:
>>>>>>>>>>>> Hi.
>>>>>>>>>>>> If I don't know any group names, there is a way to find the
>>>>>>>>>>>> clusters currently instantiated in my network?
>>>>>>>>>>>> Thanks
>>>>>>>>>>>>
>>>>>>>>>>>> Emanuele
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> Email.it, the professional e-mail, gratis per te:
>>>>>>>>>>>> http://www.email.it/f
>>>>>>>>>>>>
>>>>>>>>>>>> Sponsor:
>>>>>>>>>>>> Ti vestiamo dalla testa ai piedi e anche sotto se lo vuoi !
>>>>>>>>>>>> Clicca su www.grandinettisport.com
>>>>>>>>>>>> * Clicca qui:
>>>>>>>>>>>> http://adv.email.it/cgi-bin/foclick.cgi?mid=7502&d=15-2
>>>>>>>>>>>>
>>>>>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>>>>>
>>>>>>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>>>>
>>>>>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>>>
>>>>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>>
>>>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Email.it, the professional e-mail, gratis per te:
>>>>>>>> http://www.email.it/f
>>>>>>>> Sponsor:
>>>>>>>> Cerchi un gioiello speciale ad un prezzo davvero imbattibile?
>>>>>>>> Sceglilo su
>>>>>>>> * A&A Diamonds.com e lo riceverai a casa tua in 24 ore!
>>>>>>>> * Clicca qui:
>>>>>>>> http://adv.email.it/cgi-bin/foclick.cgi?mid=7476&d=16-2
>>>>>>>>
>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>
>>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>>
>>>>>>>
>>>>>>> ---------------------------------------------------------------------
>>>>>>>
>>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Email.it, the professional e-mail, gratis per te:
>>>>>> http://www.email.it/f
>>>>>>
>>>>>> Sponsor:
>>>>>> Vuoi un superCELL? Scarica subito la tua SuperHIT preferita!
>>>>>> * Clicca qui:
>>>>>> http://adv.email.it/cgi-bin/foclick.cgi?mid=7517&d=16-2
>>>>>>
>>>>>> ---------------------------------------------------------------------
>>>>>>
>>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>>
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>>
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Email.it, the professional e-mail, gratis per te: http://www.email.it/f
>>>
>>> Sponsor:
>>> SuperHIT sul cellulare! La tua musica preferita sempre con te.
>>> * Clicca qui: http://adv.email.it/cgi-bin/foclick.cgi?mid=7514&d=16-2
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
>> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>>
>>
>
>
>
> --
> Email.it, the professional e-mail, gratis per te: http://www.email.it/f
>
> Sponsor:
> Corri con le migliori scarpe sportive, verso la primavera!! Visita
> www.grandinettisport.com * Clicca qui:
> http://adv.email.it/cgi-bin/foclick.cgi?mid=7504&d=16-2
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe_at_shoal.dev.java.net
> For additional commands, e-mail: users-help_at_shoal.dev.java.net
>