Are there any early estimates of the expected %age increase in something like logged-in daily active users?

@SToyofuku-WMF to add charts and graphs from the DB side, courtesy of Amir

When I talked to Traffic about this topic earlier in the year, the concerns were mainly around potential increase in logged-in user traffic. Since then, the design of this first Reading Lists experiment has changed. We're planning to release the initial version of Reading Lists to a max 200,000 existing logged-in users spanning 6 wikis: enwiki, frwiki, arwiki, idwiki, viwiki, zhwiki.

Given the very limited nature of this rollout, @CDanis , we're not expecting any increase in logged-in user traffic from this specific experiment any more. We do plan to encourage users to create accounts to use features like Reading Lists in the future, and we'll work closely with Traffic & SRE to determine the scale of that future experiment, potentially some time in Q3 or Q4.

But for now, my guess is that we don't have to monitor impact on traffic at this point (but it would be great to verify this @CDanis). We've already consulted with Amir on the potential DB impact as Steph mentioned above.

Sounds good to me @Jdrewniak ! Thanks :)

DB config:
https://noc.wikimedia.org/db.php?dc=eqiad (unclear where x1 is, but not immediately necessary)

X1 graphs:
https://grafana.wikimedia.org/d/000000278/mysql-aggregated?orgId=1&var-site=eqiad&var-group=parsercache&var-group=core&var-shard=x1&var-role=$__all&from=now-6h&to=now&timezone=utc

X1 cluster:
https://orchestrator.wikimedia.org/web/cluster/alias/x1

The ticket that makes us less worried about user properties table:
https://phabricator.wikimedia.org/T406724

Thanks for those graphs @SToyofuku-WMF , let's monitor those when we launch the experiment. Given that we're not creating any additional accounts with this experiment, that's seems sufficient.