Since version 1.6.23, memcached comes with a built in proxy (not by default yet). We could investigate if we may want to switch from mcrouter to Memcached Proxy.
What?
Memcached Proxy is a cache pool management tool incorporated into the memcached daemon. It separates clients from memcached server pools for easy management, scalability, and adaptability. It can be configured using Lua, while it comes with some standard libraries for common scenarios. The proxy can manage server pools locally or across datacenters/availability zones, and amongst other things, it can replicate traffic, route keys to different pools based on predefined rules etc.
Why?
While mcrouter has served us very well, it is not a community project but a facebook project, with all the prons and cons that come with this.
How?
If we finish up T346690, we could create a small memcached proxy deployment and test it on mediawiki deployment.
Documentation