What is the max alert retention period in Event Mgmt? Is it ok to retain alerts for more than 90 days?

[EssnZilla]

OOB retention for alerts is 90 days and for events its 5 days.

Can these values be increased? what is the affect on performance if i increase the retention period for alerts to 180 days? and event to 30 days?

[EssnZilla]

Thank you Ryan