Default calculated values for a virtual machine created with 2496MB memory (2443MB as far as ansible is concerned)

php.ini

; Maximum amount of memory a script may consume (128MB)
; http://php.net/memory-limit
memory_limit = 128M

prefork.conf

# prefork MPM
# StartServers: number of server processes to start
# MinSpareServers: minimum number of server processes which are kept spare
# MaxSpareServers: maximum number of server processes which are kept spare
# MaxClients: maximum number of server processes allowed to start
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule mpm_prefork_module>
    StartServers          5
    MinSpareServers       5
    MaxSpareServers       10
    MaxClients            23
    ServerLimit           23
    MaxRequestsPerChild   1000
</IfModule>