Re: [Hawkular-dev] scope of the agent design

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi John, On 03/11/2015 06:57 PM, John Mazzitelli wrote: I think the "what" needs to be defined before the "how", hence my questions. I take it that the agent is a "metrics collector". In my mind, it has no power to influence the state of the application or machine: it just collects and reports. Collecting to me means: take a snapshot of the moment and store it somewhere locally. Reporting to me means: take the stored snapshots and send it to a server somewhere. Once the server ACKs that it received, those snapshots are then removed from the local storage. Is "inventory" also a definition from RHQ? Or can I assume that "inventory" is "a thing that can be measured"? Like, "CPU" is an item on the inventory, as well as "Memory" and "Web Application 'Acme Travel System'". Yes. For web applications, via a Java Agent, as this would allow to detect "everything" that runs on the JVM. With that, it would be possible to detect deployments and its capabilities (JAX-RS, EJBs, Batch jobs, ...) and apply specific metrics to specific facets. For instance, for a JAX-RS application, there could be a collection of metrics per endpoint (average/mean/max/min response times). For EJBs, the same but per "business method". For JPA, it could collect the time spent on the DB (and perhaps even aggregate that by prepared statement). For system resources, I think it would need to be something that would run with (high?) privileges, so that it can take data like disk space in all partitions, CPU/memory/swap usage, network traffic, ... Do you have a sample use case for this? What I can imagine is: web application 'Acme Travel System' is deployed but the agent can't detect it automatically. Something tells the agent that there's a web application deployed. But still, if it cannot see it, how can it measure it? Not sure I understand the question, but I'd say yes: as an application developer, I want to be able to add custom metrics, such as "# of logged in users", "# of registrations", "# of checkouts" and so on. - - Juca.