Hi all, Yesterday I filed a JIRA (HADOOP-9090<https://issues.apache.org/jira/browse/HADOOP-9090>) to propose a refactoring of the MetricsSystemImpl class - the default (only?) implementation of the Metrics2 system - to factor out some common code in a base class and have another simple implementation that just does on-demand publishing of metrics instead of the default periodic publishing. The main motivation for filing this JIRA and the attached patch is that we (Microsoft) have a need to publish metrics out of short-lived processes (think "hadoop fs -ls") and the periodic behavior of the default implementation doesn't really work well for those. We could write our own metrics system implementation (and we'll probably do that in the short term) but that would mean duplicating a lot of great code that's already in the MetricsSystemImpl class, hence the proposal to factor out the common code into a base class.
Does that sound reasonable? Please comment on the JIRA directly or reply here - if the proposal sounds awful (or great) or there's something I'm fundamentally missing I'd love to hear that feedback. Thanks! Mostafa
