Do we have any usage of metrics2 currently in 0.94? If not, it seems odd to deprecate existing metrics implementations. Aside from whether or not we should deprecate in a point release, normally deprecation happens when the new implementation you're supposed to move to has already been added, so that you have both old and new versions in parallel.
If we deprecate existing metrics in 0.94 and only have metrics2 implementation in 0.96, that gives no chance for switching back and forth between the two in the same release. While most of the metrics classes can be seen as private, I think that MetricsContext is arguably a public interface. Implementing your own MetricsContext to plugin to your own monitoring system is not that crazy a thing to do. So if that is changing in the move from metrics to metrics2, I think it would be hurting our users to not have both implementations available at the same time. On Tue, Jul 10, 2012 at 1:45 AM, Ted Yu <[email protected]> wrote: > In another email thread 'HBase 0.94.1', Lars has kindly accepted the motion > that deprecating current metric classes be done for 0.94.1 > > Since 0.94.1 contains critical bug fixes, I want to get public opinion on > closing this poll earlier than Friday. > > Thanks for the understanding. > > On Mon, Jul 9, 2012 at 9:05 PM, Otis Gospodnetic <[email protected] >> wrote: > >> +1 for deprecating and moving to metrics2 faster. >> I'd normally make the same argument about deprecating that Lars H. made, >> but I think current HBase metrics really need improvement, so if I had >> voting power I'd vote to drop old stuff and move to metrics2 ASAP. >> >> Otis >> >> ----- Original Message ----- >> > From: Ted Yu <[email protected]> >> > To: [email protected] >> > Cc: >> > Sent: Saturday, July 7, 2012 10:23 AM >> > Subject: deprecating (old) metrics in favor of metrics2 framework >> > >> > Hi, >> > See the following comment for background: >> > >> https://issues.apache.org/jira/browse/HBASE-4050?focusedCommentId=13408679&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13408679 >> > >> > metrics2 framework is in both hadoop 1.0 and hadoop 2.0 >> > We would like to migrate to metrics2 framework. But maintaining two >> metrics >> > frameworks in HBase is costly and results in lower readability. >> > >> > However, if you have cluster monitoring tool that depends on (old) >> metrics >> > framework, we want to give you smooth migration experience. >> > >> > Please provide your opinions on whether (old) metrics framework should be >> > deprecated in 0.94 or in 0.96. >> > >> > Thanks >> > >>
