Due to the phabricator update (T156373) we experienced a crash on all the m3 replicas because of a MariaDB bug (T156373#2973202 T156373#2973962).
We were lucky that the master and the eqiad dbstores were running an old non affected version of Mariadb, so they survived the crash.
However, we have started to wonder if it is really necessary to have m3 on the dbstores servers, specially on dbstore1002 (which is the non delayed replica).
We assume it is not needed at all on codfw and we are going to drop it from there, but we'd like to know if m3 in dbstore1002 is being used or it can be dropped there too.
Any thoughts from Analytics team?