HAProxy using 100% CPU 200 concurrent connections - ssl

Question

I've recently started to load test my app and found that HAProxy for some reason is not able to handle a lot of concurrent connections.
Im only using HAProxy to load balance my SSL traffic, for non-ssl (99% of my traffic is ssl) i use nginx.
I have tested my setup on blitz.io and when sending traffic to non-ssl (200 concurrent) i get no timeouts or errors. However when doing the same test over SSL (which HAProxy handles) i immediately get 100% CPU and requests are timing out.
This leads me to believe there is something wrong in my HAProxy config.
Below is my config, any ideas what could be wrong?
Oh and i am running this on a medium EC2 CPU optimized instance
My haproxy.cfg:
global
maxconn 400000
ulimit-n 800019
nbproc 1
debug
daemon
log 127.0.0.1 local0 notice
defaults
mode http
option httplog
log global
stats enable
stats refresh 60s
stats uri /stats
maxconn 32768
frontend secured
timeout client 86400000
mode http
timeout client 120s
option httpclose
#option forceclose
option forwardfor
bind 0.0.0.0:443 ssl crt /etc/nginx/ssl/ssl-bundle.pem
acl is_sockjs path_beg /echo /broadcast /close # SockJS
acl is_express path_beg /probe /loadHistory /activity # Express
use_backend www_express if is_express
use_backend sockjs if is_sockjs
default_backend www_nginx
backend tcp_socket
mode http
server server1 xx.xx.xx.xx:8080 check port 8080
backend www_express
mode http
option forwardfor #this sets X-Forwarded-For
timeout server 30000
timeout connect 4000
server server1 xx.xx.xx.xx:8008 weight 1 maxconn 32768 check
backend sockjs
mode http
option forwardfor #this sets X-Forwarded-For
timeout server 30000
timeout connect 4000
server server1 xx.xx.xx.xx:8081 weight 1 maxconn 32768 check
backend www_nginx
mode http
option forwardfor #this sets X-Forwarded-For
timeout server 30000
timeout connect 4000
server server1 localhost:80 weight 1 maxconn 8024 check
listen stats :8181
mode http
stats enable
stats hide-version
stats realm Haproxy\ Statistics
stats uri /
stats auth helloxx:xx