Issue with Haproxy Reload (no replies)

Hi,

We are using Haproxy on top of Mesos cluster, We are doing dynamic reloads
for Haproxy based on marathon events (50-100 times in a day). We have
nearly *300 applications* that are running on Mesos (300 virtual hosts in
Haproxy). When we do dynamic reloads, Haproxy is taking long time to reload
Haproxy, we observed that for 50 applications takes *30-40secs to reload
Haproxy*. We have a single config file for Haproxy, when we do reload all
the applications are getting reloaded (Front-ends), this causing downtime
of all applications. Is there anyway to reduce the downtime and impact on
end-users.

We tried this scenario,
"
http://engineeringblog.yelp.com/2015/04/true-zero-downtime-haproxy-reloads.html
"

By this if user requests while reload, the requests are queued and serving
after reload.

But if we do multiple reloads one after another, *HaProxy old processes
persist even after reloading the HaProxy service*, this is causing the
serious issue.

root 7816 0.1 0.0 20024 3028 ? Ss 03:52 0:00
/usr/sbin/haproxy -f /etc/haproxy/haproxy.cfg -p /var/run/haproxy.pid -D
-sf 6778
root 7817 0.0 0.0 20024 3148 ? Ss 03:52 0:00
/usr/sbin/haproxy -f /etc/haproxy/haproxy.cfg -p /var/run/haproxy.pid -D
-sf 6778

Is there any solution stop the previous process once after it serving the
request.


Can we *separate the configurations based on front-ends like in Nginx*, so
that only those apps will effect if there is any changes in backend.

Thank you.

--
Best Regards,
Rajeev Jaggavarapu,​
Paxcel Labs.