This could also cause network issues due to purging.
Related Gerrit Patches:
|mediawiki/core : master||Limit DELETE in purgeExpiredRestrictions() and use primary key|
There were hundreds of queries in the last hour, the largest ones taking 15 seconds:
db1049 wikiuser dewiki mw1226 - 195772733 59961145543 15s 2016-05-17 06:29:54 DELETE /* Title::purgeExpiredRestrictions Doc Taxon */ FROM `page_restrictions` WHERE (pr_expiry < '20160517062948')