on systems with 4GB memory, Kamailio can serve a population over 300 000 online subscribers
<from: https://www.kamailio.org/w/features/ >

Test bed:

CPU: 4 cores , 4G RAM

Kamailio 5 with Mysql.

Test source：another server running SIPp

10k subscriber in Mysql . 6000 Register Per Second , reuse 10k user to register , it works fine. If register 50 every second for per user it seem 300 k subscribers should work.

(about 300% cpu used of totally 400% cpu. All requests finished without retransmit and fail. )

add 90k subscriber into Mysql .

100k subscirbers in Mysql . 1000 Register Per Second , a lot of failure and can not work .

(cpu are not used much at that time. IO is not high.)

My question :

What is the root cause of bad performance when there is 100k subscribers' data in the Mysql database.

How can I deploy a kamailio with 300k subscriber in database, and support 6000 register per second at the same time ?

Maybe use ram database instead of Mysql?

Thanks with regards,

David