Performance Question

I’ve figured I would find answers to this in the archive, but have been unable to. So, I appreciate the time.

I am setting up an haproxy instance in front of some tomcat instances. As a test, I ran ab against one of the tomcat instances directly with an increasing number of concurrent connections. I then repeated the same test with haproxy fronting 4 tomcat servers. I was hoping to see that the haproxy setup would perform a higher number of requests per second and hold that higher number with increasingly high traffic. Unfortunately, it did not.

Hitting the tomcat servers directly, I was able to get in excess of 3700 rqs/s. With haproxy in front of that tomcat instance and three others (using roundrobin), I never surpassed 2500. I also did not find that I was able to handle an increased amount of concurrency (both started giving errors around 20000).

I have tuned the tcp params on the linux side per the suggestions I have seen on here. Are there any other places I can start to figure out what I have wrong in my configuration??

Thanx,
LES ———

haproxy.cfg

global

        #log loghost    local0 info
        maxconn 500
        nbproc 4
        stats socket    /tmp/haproxy.sock level admin
defaults
        log global
        clitimeout 60000
        srvtimeout 30000
        contimeout 4000
        retries 3
        option redispatch
        option httpclose
        option abortonclose

listen stats 192.168.60.158:8081
        mode            http
        stats          uri /stat  #Comment this if you need to specify diff stat path for viewing stat page
        stats enable  
listen erp_cluster_https 0.0.0.0:81
       mode http
       balance roundrobin
       option forwardfor except 0.0.0.0
       reqadd X-Forwarded-Proto:\ https
       cookie SERVERID insert indirect
       server tomcat01-instance1 192.168.60.156:8080 cookie A check
       server tomcat01-instance2 192.168.60.156:18080 cookie A check
       server tomcat02-instance1 192.168.60.157:8080 cookie A check
       server tomcat02-instance2 192.168.60.157:18080 cookie A check