After increasing the number of maximum possible connections to the mysql database?

Question

MySQL

Hello.
zabbix 3.2
increased the connection pool from 256 to 400 for the mysql database (percona) after the error began to be reproduced

•	mysqli_query(): (70100/1317): Query execution was interrupted [zabbix.php:21 > require_once() > ZBase->run() > ZBase->processRequest() > CView->getOutput() > include() > make_status_of_zbx() > get_status() > DBselect() > mysqli_query() in include/db.inc.php:404]
•	Error in query [SELECT COUNT(DISTINCT t.triggerid) AS cnt,t.status,t.value FROM triggers t WHERE NOT EXISTS (SELECT f.functionid FROM functions f JOIN items i ON f.itemid=i.itemid JOIN hosts h ON i.hostid=h.hostid WHERE f.triggerid=t.triggerid AND (i.status<>0 OR h.status<>0)) AND t.flags IN (0,4) GROUP BY t.status,t.value] [Query execution was interrupted]

Is this related to this, if not, and what to do in this situation (besides returning it back)?