Core: added a warning about reusing connections.

Previously, reusing connections happened silently and was only
visible in monitoring systems.  This was shown to be not very user-friendly,
and administrators often didn't realize there were too few connections
available to withstand the load, and configured timeouts (keepalive_timeout
and http2_idle_timeout) were effectively reduced to keep things running.

To provide at least some information about this, a warning is now logged
(at most once per second, to avoid flooding the logs).
2 files changed
tree: f0e06f9c7737808166996b689102b96b5cb8cbe1
  1. .hgtags
  2. auto/
  3. conf/
  4. contrib/
  5. docs/
  6. misc/
  7. src/