Hi, Thanks Chris for the feedback. When writing KIP-877 I already had this KIP in mind. I'm finally getting to tackle it now,
1. I briefly considered it but wasn't sure if there is a need for it. My main concern is the volume of metrics. In my experience users often collect all metrics (or none but that's a different story) and this would effectively double the number of series. As there are metric series per partition and consumer group that can quickly escalate. Also by having a boolean, I though it would kind of trigger people to flip the switch and migrate, instead of just enabling both and running like this till 5.0. 2. That's right. Only MirrorSourceConnector and MirrorCheckpointConnector have metrics. I've added that to the KIP. 3. That's a good suggestion. I've added it to the KIP. 4. You caught me red handed copy pasting from another KIP. I've removed the "Update Mode" as it's not relevant for connector configurations. Thanks, Mickael On Sat, Feb 14, 2026 at 5:17 PM Chris Egerton <[email protected]> wrote: > > Hi Mickael, > > Thanks for the KIP! While reviewing 877 I remember wondering if/when we'd > see this follow-up. I think it's a good idea to align the MM2 metrics with > the 877 style and eat some of our own dogfood as well. Thoughts: > > 1. Can we support a dual-write mode to reduce risk during upgrades? Can > elaborate more on the motivation here if necessary. > > 2. I take it the heartbeat connector and client utils don't report any > custom metrics? If so, would be nice to see that called out, and if not, > I'd expect to see them mentioned in either a rejected alternatives or > future work section. > > 3. Guessing we'll want to log some kind of notice to users who are still > using the legacy metrics? I don't care (at this point) whether it's at info > or warn level but it'd be nice to know that we plan to emit some kind of > message. > > 4. (Nit) I think the "Update Mode" attribute for the new property may have > been left in accidentally? If not, would you mind explaining what it means > for a connector? > > Cheers, > > Chris > > On Fri, Feb 13, 2026, 11:19 Mickael Maison <[email protected]> wrote: > > > Hi, > > > > I'd like to start a discussion about KIP-1280: > > https://cwiki.apache.org/confluence/x/a4s8G > > > > This proposes updating the MirrorMaker connectors to use KIP-877 to > > register their metrics. > > > > Let me know if you have any questions or feedback. > > > > Thanks, > > Mickael > >
