Some improvements for handling of many connections for MPM event:

- Process lingering close asynchronously instead of tying up worker threads
  (based on patch by Jeff Trawick).

- If the number of connections of a process is above

     threads_per_child  +  WORKER_OVERCOMMIT * (idle_workers - 1)

  (WORKER_OVERCOMMIT is fixed at 2, at the moment), or if all workers are busy,
  don't accept new connections in that process. Such a dynamic connection limit
  is necessary because we may have both async and non-async (ssl) connections.
  WORKER_OVERCOMMIT should be a config option.

- Don't count idle workers of not-accepting processes against MinSpareThreads,
  so that the parent will spawn new processes when necessary.

- If we receive a keep-alive request while all workers are busy, don't block
  but close the connection immediately so that the client will re-connect to a
  different process.

Related changes:

- Log what is going on at trace loglevels.
- Remove the bypass_push poll type flag, this code cannot be hit anymore
  (if it ever could?).
- Add some macro helpers for dealing with timeout queues.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1137358 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 7 insertions, 0 deletions

diff --git a/CHANGES b/CHANGES
index 3465138844..03e72a387b 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2,6 +2,13 @@
 
 Changes with Apache 2.3.13
 
+  *) mpm_event: If the number of connections of a process is very high, or if
+     all workers are busy, don't accept new connections in that process.
+     [Stefan Fritsch]
+
+  *) mpm_event: Process lingering close asynchronously instead of tying up
+     worker threads. [Jeff Trawick, Stefan Fritsch]
+
   *) mpm_event: If MaxMemFree is set, limit the number of pools that is kept
      around. [Stefan Fritsch]