title: Haproxy URL route not work corrent
body: <p>I have a API web server, there are two version api coexist, they are routed by url path, which is /shine/v7 and /shine/v8.</p>
  
  <p>I made this by haproxy, but when I request /shine/v7/admin, it sometimes went to shine_v8_backend, and sometimes went to shine_v7_backend, I don't know why this happend, is anyone can help me?</p>
  
  <p>there is my haproxy.conf</p>
  
  <pre><code>global
      log 127.0.0.1   local0
      log 127.0.0.1   local1 notice
      maxconn 4096
      daemon
  
  defaults
      log     global
      option  http-server-close
  
  frontend http *:5000
      mode tcp
      timeout client 86400000
  
      default_backend shine_v8_backend
      acl shine_v7    path_dir /shine/v7
      use_backend     shine_v7_backend    if shine_v7
  
  
  backend shine_v8_backend
      mode tcp
      option httpclose
      balance roundrobin
      timeout server 86400000
      timeout connect 5000
      server host_0 127.0.0.1:5001
  
  backend shine_v7_backend
      mode tcp
      option httpclose
      balance roundrobin
      timeout server 86400000
      timeout connect 5000
      server host_0 127.0.0.1:5002
  </code></pre>
  
  <p>I try to request /shine/v7/admin many times, there is the logs</p>
  
  <pre><code>$ sudo haproxy -f haproxy.conf -d
  Available polling systems :
       kqueue : pref=300,  test result OK
         poll : pref=200,  test result OK
       select : pref=150,  test result FAILED
  Total: 3 (2 usable), will use kqueue.
  Using kqueue() as the polling mechanism.
  00000000:http.accept(0004)=0006 from [127.0.0.1:55026]
  00000000:shine_v7_backend.srvcls[0006:0007]
  00000000:shine_v7_backend.clicls[0006:0007]
  00000000:shine_v7_backend.closed[0006:0007]
  00000001:http.accept(0004)=0006 from [127.0.0.1:55028]
  00000001:shine_v8_backend.srvcls[0006:0007]
  00000001:shine_v8_backend.clicls[0006:0007]
  00000001:shine_v8_backend.closed[0006:0007]
  00000002:http.accept(0004)=0006 from [127.0.0.1:55030]
  00000002:shine_v7_backend.srvcls[0006:0007]
  00000002:shine_v7_backend.clicls[0006:0007]
  00000002:shine_v7_backend.closed[0006:0007]
  00000003:http.accept(0004)=0006 from [127.0.0.1:55032]
  00000003:shine_v8_backend.srvcls[0006:0007]
  00000003:shine_v8_backend.clicls[0006:0007]
  00000003:shine_v8_backend.closed[0006:0007]
  00000004:http.accept(0004)=0006 from [127.0.0.1:55034]
  00000004:shine_v7_backend.srvcls[0006:0007]
  00000004:shine_v7_backend.clicls[0006:0007]
  00000004:shine_v7_backend.closed[0006:0007]
  </code></pre>