[infinispan-dev] Including CENTRAL_LOCK in our stacks, COUNTER

[Sanne Grinovero]

Having my app introduce this on the stack leads to other kinds of
problems, I think it would be way simpler if the protocols where
always available on each participating node.

One of my problems is that Hibernate Search might get deployed on one
node but not be deployed (yet or at all) on another node; it's exactly
to solve this problem that I'm thinking to use the LockService: to
reliably elect a single master node for each index without being
coupled to the notion of View, as that doesn't necessarily match with
the deployed applications and available services I have on each node.
There is a strong requirement that we don't have more than one master
node at any time, but a new node needs to be elected if the elected
one fails so LockService is looking good for that.

The Coordination election isn't good enough as
 - that node might not have Search running
 - I'd like to distribute the load of different indexes on different
nodes, basically hashing on the index name to suggest a favourite
node.

So if I have to add the stack at runtime.. the nodes not having my
services deployed yet won't have the protocol, I assume CENTRAL_LOCK
won't work properly if some nodes - especially the coordinator - don't
have it installed?

I already have the option to create a new Channel and bypass any
trouble, the point is I'd like to reuse the single channel, both for
efficiency reasons but also to guarantee consistent views, consistency
with mod_cluster, etc..

Sanne

On 17 October 2012 11:57, Bela Ban <bban at redhat.com> wrote:
> Paul: is it possible to create a new stack dynamically in AS7 ? E.g. through
> use of programmatic configuration ?
>
> Sann: then you could create your stack dynamically, as needed...
>
>
> On 10/17/12 12:28 PM, Sanne Grinovero wrote:
>>
>> Hi all,
>>
>> I'm still in a prototyping phase, but for the next big feature of
>> Hibernate Search&  Infinispan Query it looks like the LockService from
>>
>> JGroups would be exactly what I need.
>>
>> My only concern about using it is that people will have to reconfigure
>> JGroups from Infinispan, or even worse to reconfigure the stack in
>> AS7.
>>
>> Would it be possible to include this in our default stacks? Including
>> the one provided by AS7 ?
>>
>> I have a very similar requirement for Hibernate OGM to rely on COUNTER
>> for the CounterService... same question, different use case.
>>
>> Regards,
>> Sanne
>
>
> --
> Bela Ban, JGroups lead (http://www.jgroups.org)