Number of agents login limit

Hi I am using Asterisk 11 in vicidial call center suite. I have very good hardware which can support upto 300 agents, but calls issues start and slow web service when more than 50 agents login at the same time. This limit is due to the performance of the software. How can I increase the number of login agents to take calls, without any malfunctioning of the software service. I have researched a lot in this regard in vicidial forums, but I thought I must escalate to Asterisk,because issue is at your end. I will be thankful for any guidance and support.

Asterisk 11 end of life 2017-10-25, so if you having issue with Asterisk upgrade to the LTS version, vicidial run many scripts on background and a havy usage of the DB and apache, I suggest you use vicidial clustering a dedicated web server on the vicidial end, this issue it is not related to Asterisk