For example, I found on db1070 2 long running queries:
Server Connection User Client Database Time
db1070 51133099 wikiuser mw1256 wikidatawiki 19h
SELECT /* Wikibase\Repo\Store\Sql\SqlEntitiesWithoutTermFinder::getEntitiesWithoutTerm */ page_title AS `entity_id_serialization` FROM `page` LEFT JOIN `wb_terms` ON ((((term_entity_id = REPLACE(page_title, 'Q', '')) AND term_entity_type = 'item' AND page_namespace = '0') OR ((term_entity_id = REPLACE(page_title, 'P', '')) AND term_entity_type = 'property' AND page_namespace = '120')) AND term_type = 'description' AND term_language = 'fr') WHERE (term_entity_type IS NULL) AND page_is_redirect = '0' AND page_namespace IN ('0','120') ORDER BY page_id DESC LIMIT 51
db1070 51146589 wikiuser mw1256 wikidatawiki 19h
SELECT /* Wikibase\Repo\Store\Sql\SqlEntitiesWithoutTermFinder::getEntitiesWithoutTerm */ page_title AS `entity_id_serialization` FROM `page` LEFT JOIN `wb_terms` ON ((((term_entity_id = REPLACE(page_title, 'Q', '')) AND term_entity_type = 'item' AND page_namespace = '0') OR ((term_entity_id = REPLACE(page_title, 'P', '')) AND term_entity_type = 'property' AND page_namespace = '120')) AND term_type = 'description' AND term_language = 'fr') WHERE (term_entity_type IS NULL) AND page_is_redirect = '0' AND page_namespace IN ('0','120') ORDER BY page_id DESC LIMIT 51They where running on db1070 (nice because it is the vslow slave), but they where running with the web request user, not with the dumps or the admin user, which means they will be killed in 300 seconds (not being killed is a bug, and that will be corrected immediately).
The request is to identify what those queries are- if they should be interactive responses, check its execution, as it should be under 300 seconds; if it is non-interactive, they should be probably run from terbium and with a different user so they are not killed. There is anyway a maximum execution time of 24 hours, and only on special cases, for queries that are done once a month or so on enwiki.