hi gabriel, i think yes, i did what you told, i use show processlist / information_schema.processlist to get id and after kill (i don't know if there's another solution to get query id of other process)
what happened?
connection 1) big select...
connection 2)show processlist
connection 2) kill connection 1 id (i take +- 1 second between show processlist and this command)
connection 1) other query
connection 1) killed
in other words, i killed the second query of connection 1, not the first one