We already have v1.6.6 packaged for Buster so we can consider upgrading to to this version, with caution.
Note: " If you have critical infrastructure on memcached, please roll this out slowly if possible."
- Install memcached 1.6.6 to 1 server in codfw and run tests using mwdebug2002
- Install memcached 1.6.6 to 1 server in eqiad and monitor
- Rollout to codfw
- Rollout to eqiad, one server at a time