very low requests per second rate with option forceclose (no replies)

Hi,

I need help with my haproxy config. I have been asked to disable keepalive in haproxy.
As soon as I use "option forceclose” the requests per second rate mesured with apachebench
goes down form like 1000 requests per second to 25 requests per second.

frontend w-test-kon
bind *:8000
bind *:8001 ssl crt /etc/ssl/private/wildcard.w.pem
maxconn 4096000
default_backend web1

frontend w-test-koff
option forceclose
no option http-keep-alive
bind *:8002
bind *:8003 ssl crt /etc/ssl/private/wildcard.w.pem
maxconn 4096000
default_backend web1

backend web1
mode http
balance roundrobin
http-reuse always
server web1-ip1 192.168.2.11:80 check source 192.168.2.211
option httpchk
maxconn 4096000
http-response set-header Strict-Transport-Security "max-age=16000000; includeSubDomains; preload;"

Without forceclose:

$ ab -v 1 -k -c 10 -n 1000 https://w:8001/test/index.html | grep -e Requests -e Complete -e Failed
Complete requests: 1000
Failed requests: 0
Requests per second: 1112.29 [#/sec] (mean)

With foreclose:

$ ab -v 1 -k -c 10 -n 1000 https://w:8003/test/index.html | grep -e Requests -e Complete -e Failed
Complete requests: 1000
Failed requests: 0
Requests per second: 25.86 [#/sec] (mean)

Whatever I configure as soon as I disable keepalive I am down to 24-45 requests per second.

Anyone an idea what I am doing wrong?

Thanks in advance!

Stefan