On 21 October 2014 11:40, Bertrand Delacretaz <bdelacre...@apache.org> wrote: > Hi Amit, > > On Tue, Oct 21, 2014 at 11:49 AM, Amit.. Gupta. <amitg...@adobe.com> wrote: >> ...I would like to add API to capture application-level metrics. The api >> is inspired by Yammer Metrics [0]... > > I'll repeat my SLING-4080 comments: why reinvent this here?
Yammer metrics went through some breaking API changes between 3.0 and 3.1. It wasnt designed for OSGi and it is debatable if those changes conform to an OSGi notion of semantic versioning. I may have prompted Amit to pursue the shim API as I had to re-instrument everywhere upgrading between 3.0 and 3.1 which was real pain. I think the shim API eliminates that issue. > > I'm not against that if you can provide compelling reasons, but the > Sling codebase is big enough that we should try to keep it focused on > Sling's "core business", and I don't think metrics are part of that. Agreed, we must not re-implement Yammer Metrics (or any other metrics impl), there is some serious production experience deep inside that jar. One reason for the SPI is that Yammer Metrics uses sun.misc.Unsafe and does implements a 64bit Stripe class that bind to the Sun JDK. There are pointers to what needs to be done OpenJDK. > > Also, as Ian says we need metrics all the way down to the Oak level, > so the effort might be better invested in making the necessary > adaptions to use a good metrics library inside both projects. Or putting this simple API somewhere it can be used by both projects ? Best Regards Ian > > -Bertrand
