I am trying to configure HAProxy to do load balancing for a custom webserver I created. Right now I am noticing an increasing delay with HAProxy as the size of the return message increases. For example, I ran four different tests, here are the results:
Response 15kb through HAProxy:
Avg. response time: .34 secs
Transacation rate: 763 trans/sec
Throughput: 11.08 MB/sec
Response 2kb through HAProxy:
Avg. response time: .08 secs
Transaction rate: 1171 trans / sec
Throughput: 2.51 MB/sec
Response 15kb directly to server:
Avg. response time: .11 sec
Transaction rate: 1046 trans/sec
throughput: 15.20 MB/sec
Response 2kb directly to server:
Avg. Response time: .05 secs
Transaction rate: 1158 trans/sec
Throughput: 2.48 MB/sec
All transactions are HTTP requests. As you can see, there seems to be a much bigger difference between response times for when the response is bigger, than when it is smaller. I understand there will be a slight delay when using HAProxy. Not sure if it matters, but the test itself was run using siege. And during the test there was only one server behind the HAProxy(the same that was used in the direct to server tests). Here is my haproxy.config file:
global
log 127.0.0.1 local0
log 127.0.0.1 local1 notice
maxconn 10000
user haproxy
group haproxy
daemon
#debug
defaults
log global
mode http
option httplog
option dontlognull
retries 3
option redispatch
option httpclose
maxconn 10000
contimeout 10000
clitimeout 50000
srvtimeout 50000
balance roundrobin
stats enable
stats uri /stats
listen lb1 10.1.10.26:80
maxconn 10000
server app1 10.1.10.200:8080 maxconn 5000
I couldn't find much in terms of options in this file that would help my problem. I have heard suggestions that I may have to adjust a few of my sysctl settings. I could not find a lot of information on this however, most documentation is for Linux 2.4 and 2.6 on the sysctl stuff, I am running 3.2(Ubuntu server 12.04), which seems to auto tuning, so I have no clue what I should or shouldn't be changing. Most settings changes I tried had no effect or a negative effect on performance.
Just a notice, this is a very preliminary test, and my hope is that at deployment time, my HAProxy will be able to balance 10k-20k requests/sec to many servers, so if anyone could provide information to help me reach that goal, it would be much appreciated.
Thank you very much for any information you can provide. And if you need anymore information from me please let me know, I will get you anything I can.