+1, looks quite good to me!
Jacques
From: "Jacopo Cappellato" <[email protected]>
Adrian,
thank you for the clear description and proposal; I like it very much and I
would be happy to see it in OFBiz.
Regards,
Jacopo
On Jul 14, 2012, at 12:38 PM, Adrian Crum wrote:
I have an application metrics feature working on my local copy and I was wondering if there would be any interest in including it
in the project.
A metric is a measure of average execution time. Each metric is given a unique
name.
I modified the control servlet and service dispatcher to use metrics. To add a
metric to a request, just include an XML element:
<metric name="URL: webtools/main" />
to the request map and the average response time for the URL will be maintained. Likewise, to add a metric to a service, just
include an XML element:
<metric name="Service: createMaintsFromTimeInterval" />
to the service definition and the average execution time for the service will
be maintained.
Metrics are kept in memory. There is a service to retrieve all metrics. There
is also a Web Tools page to view all metrics.
A heartbeat server could retrieve the metrics to check on server load or to
provide histograms.
The metric element has an optional threshold attribute, so some action could be taken when the metric crosses a threshold. For
example, in the following request map:
<request-map uri="ViewMetrics">
<security https="true" auth="true"/>
<metric name="URL: webtools/ViewMetrics" threshold="1000"/>
<response name="success" type="view" value="ViewMetrics"/>
<response name="threshold-exceeded" type="view" value="ServerBusy"/><!--
displays a friendly 'server busy' page -->
</request-map>
the ServerBusy view would be rendered if the average response time exceeded 1000 mS. This can be useful for providing a lively
web experience on a heavy-traffic web page.
The service dispatcher does not use the threshold. I could not think of a use case where service behavior should be modified
based on average execution time.
The metrics code is very small - two java files. Also, the modifications to the webapp component and service component are very
small.
What do you think?
-Adrian