MysqliManager::connect taking more duration


We are observing mysqli connection taking more time duration

MysqliManager::connect is showing under slowness components as its duration (in between 31,000 ms- 70,000 ms),
is this normal duration or not?
if its not, is there anyway to reduce this duration?

Our SuiteCRM Version 7.8.3 environment working with PHP7.1.7 and Mysql5.7.11-log

appreciate your help