MySQL error in file: /engine/modules/topnews.php at line 30

Error Number: 23

The Error returned was:
Out of resources when opening file '/tmp/#sql_345629_0.MAD' (Errcode: 24 "Too many open files")

SQL query:

SELECT p.id, p.date, p.short_story, p.xfields, p.title, p.category, p.alt_name FROM dle_post p LEFT JOIN dle_post_extras e ON (p.id=e.news_id) WHERE p.approve=1 AND p.date >= '2018-10-17 04:44:53' - INTERVAL 1 MONTH AND p.date < '2018-10-17 04:44:53' ORDER BY rating DESC, comm_num DESC, news_read DESC, date DESC LIMIT 0,10