Hi Matheus,
we've also been wondering about the very slow ldap response times of our slapds behind our F5s (in comparison to direct slapd connections) but we had no time to analyze the behavior in detail, yet...
...and thanks to your investigations and your report to the list we don't need to investigate into this direction any more - thank you very much!
For demonstration purposes I've uploaded a screenshot of one of our response time graphs under the following url:
http://img831.imageshack.us/img831/9277/f5nagledisabled.png
As can be seen here disabling the Nagle-Algorithm (yesterday ~ 15:45 o'clock) leads to a 5 to 6 times faster response.
Cheers Daniel P.S. BTW: also many thanks into direction to the ltb-project for providing the cacti ldap response graph templates!
On 08/24/2010 08:30 PM, Matheus Morais wrote:
Hi there,
We were having some performance troubles using OpenLDAP and F5 load balance solution from BigIP at a high concurrent enviroment. We faced the problem for one month after I discovered that those problems didn't happen when applications was pointed directly to OpenLDAP server instead of load balance VIP. After a tcpdump analysis of the packages we realize that are too many ACK comming from each request.
Last week we solved the problem unsetting Nagle's algorithm on the load balance virtual server which was causing this issue.
So, if you look yourself on a similiar situation, please check the Nagle's algorithm on the F5 configuration!
Thanks,
Matheus Morais