Fetching users slow from People Picker in SharePoint
Run the below command on all site collections in all farms to increase the response time of the people picker. stsadm -o setproperty -pn peoplepicker-searchadforests -pv "domain: test.CORP " -url " https://you stie URL/sites/sitecollection/ " if you have multiple domains, use the below command stsadm -o setproperty -pn peoplepicker-searchadforests -pv "domain: test.CORP; domain:test1.CORP " -url " https://you stie URL/sites/sitecollection/ " Change domain name and URL and execute the command in powershell