[jbossws-dev] Fwd: EndpointMetrics Refactor

[Alessio Soldano]

Hi Jim,

>
> At the beginning,  I'd like to quickly list the cons of the current
> EndpointMetrics
> implementation.
> - Because the statistics is fulfilled in RequestHandlerImpl , after the
> response is successfully
>      returned to receiver. The response related metric value could not
> be updated in time, more
>      details pleas see JBWS-3808
> - It doesn't count the one way fault correctly.
yep, we need more consistent values to be returned by metric queries.

> - It doesn't expose all the attribute in jmx.
This is not necessarily a requirement, but a nice to have.

> - If the cxf's management is enabled, user will get two different
> statistics value. One is
>      calculated  with jbossws-cxf's endpointmetrics which happens in
> RequestHandler(servlet),
>      and another one is calculated with ResponseTimeInterceptor(cxf's
> interceptor).
right, and this is possibly confusing users, while we could rely on the 
existing cxf mechanism...


> The pros of current implementation :
>   - It gives more accurate start time for each request.
>   - It is simple and doesn't need to add more interceptor/extra code in
> the runtime to collect
>       the data.

In any case, regardless of which solution we eventually end up relying 
on, we need to make the data collection as light as possible and, more 
important, we need to make sure you can disable statistics and get no 
performance degradation at all.

> >From the above analysis, one important thing we need to do is make the
> EndpintMetrics seamlessly
> work with cxf's management intercetptor and get statistics from one
> place instead of generate two
> copies from different implementation.
+1

> There is CounterRepostiry extension in cxf  which responsible for
> creating ResponseTimeCounter
> for each endpoint,  It can be the only source we get statistics for each
> endpoint.
> To get metric value from this class, we need to change following things:
> 1. Each ResponseTImeCounter(something similar to EndpointMetrics) is
> lazily created in
>      message interceptor and put in CounterReposiory with a long
> ObjectName at the moment. We
>      need to change it and add the ResponseTimeCounter for each jbossws
> endpoint , then put it in
>      CounterRepostiry with key name of endpoint name.
> 2. Change EndpointMetricsFactory abstract class to create with
> EndpointMetric with endpoint
>      parameter so the endpoint name can be used to create
> ResponseTimeCounter.
> 3. Create new EndpointMetricImpl in jbossws-cxf and get metric value
> from ResponseCounter
>     which is created for each endpoint.
> 4. Change the ResponseTimeInterceptor and allow for define the counter
> object name.
>
> Besides this , I also need to refactor the ResponseTimeInterceptor to
> make it log the process time
> more accurate(by move ResponseTimeInInterceptor before several
> interceptors ?). And also refactor
> the ResponseTimeInterceptor a bit to handle the fault message correctly.
The plan might work afaics here. The details are probably the core of 
the issue ;-) I think you can provide a prototype and we can have a look 
together. Just always keep in mind my comment above regarding 
performance and being able to disable the stats at runtime to have full 
perf.

Cheers
Alessio

-- 
Alessio Soldano
Web Service Lead, JBoss