I'm quite not sure too. Its a attractive feature, but on the other hand it will 
open more issues / problems. I have "kiss" in my mind (keep it stupid and 
simple). 

- Alex 

--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF

On Jun 8, 2012, at 7:09 AM, Ralph Goers wrote:

> Can I just say absolutely yes?  I'm not clear on what issues zookeeper 
> introduced, but the concept of having a central configuration is very 
> appealing.  I can definitely say that this is one of the items that will 
> delay my employers transition from 0.9.x to 1.x.
> 
> Ralph
> 
> On Jun 7, 2012, at 3:18 PM, Eric Sammer <[email protected]> wrote:
> 
>> Flumers:
>> 
>> Flume 0.9.x supported online reconfiguration and the intention was for the
>> 1.x branch to do so as well (it doesn't yet). I wanted to start a
>> discussion around whether people are interested in this kind of
>> functionality or if simply restarting the daemon(s) was sufficient for your
>> deployment. There are two ways of thinking about it:
>> 
>> * Support reconfiguration. Agents may have multiple flows passing through
>> them and, ideally, adding new ones shouldn't interrupt existing flows.
>> Agent restarts interrupt collection and, for non-durable channels (i.e.
>> MemoryChannel), data *may* be lost. Reconfiguration will add significant
>> complexity and ultimately does not get around host level maintenance,
>> software upgrades, and the like.
>> 
>> * Do no support reconfiguration. Accept the fact that agents may go down
>> eventually, so it should be supported as a first class case. In other
>> words, embrace the idea of failure / maintenance and handle it by
>> recommending topologies of agents that include multiple agents at each tier
>> and simply roundrobin / failover where necessary. The only downside is the
>> agent tier closest to the originating source (e.g. a log4j client);
>> restarting that agent means the client application needs to be able to find
>> another agent or buffer (which impacts durability or blocks the
>> application).
>> 
>> We can optionally support some subset of online reconfiguration such as
>> only allowing new flows to be introduced or existing flows to be
>> "decommissioned," but not allow alteration of existing flows. Ultimately
>> this feature is a ton of work and adds a ton of complexity so if it's not
>> something folks are clambering for, we should spend our time worrying about
>> more pressing issues.
>> 
>> Thoughts? Comments?
>> -- 
>> Eric Sammer
>> twitter: esammer
>> data: www.cloudera.com

Reply via email to