When memmax is forced using "-m", the per-process memory limit is enforced
using setrlimit(), but this value is not used to compute the automatic
maxconn limit. In addition, the per-process memory limit didn't consider
the fact that the shared SSL cache only needs to be accounted once.
The doc was also fixed to clearly state that "-m" is global and not per
process. It makes sense because people who use -m want to protect the
system's resources regardless of whatever appears in the configuration.
This commit adds support for setting a per-server maxconn from the stats
socket. The only really notable part of this commit is that we need to
check if maxconn == minconn before changing things, as this indicates
that we are NOT using dynamic maxconn. When we are not using dynamic
maxconn, we should update maxconn/minconn in lockstep.
This doc explains how to start/stop haproxy, what signals are used
and a few debugging tricks. It's far from being complete but should
already help a number of users.
The stats part will be taken from the config doc.
