Benchmark 0.10.x

[emqplus]

Special for memory usage of qos1/2 messages.

[emqplus]

1. packets dropped

   netstat -s -p | grep buffer
   20775 packets pruned from receive queue because of socket buffer overrun
   249281 packets collapsed in receive queue due to low socket buffer
   so without logs i got up to 350K+ solid connections
   also i am getting these at times

2. eaddrnotavail

   client 34962 EXIT: {shutdown,eaddrnotavail}
   client 34959 EXIT: {shutdown,eaddrnotavail}

3. server kernel

   fs.file-max = 1000000
   net.core.somaxconn = 65536
   net.ipv4.ip_local_port_range = 500 65535
   net.nf_conntrack_max = 1000000
   net.netfilter.nf_conntrack_max = 1000000
   net.ipv4.tcp_rmem = 4096 4096 16777216
   net.ipv4.tcp_wmem = 4096 4096 16777216

4. client kernel

   sysctl -w net.ipv4.ip_local_port_range="500 65535"
   echo 1000000 > /proc/sys/fs/nr_open

[emqplus]

Done in 0.12.0: https://github.com/emqtt/emqttd/wiki/benchmark-for-0.12.0-release