Problem: Apache server will stay up for random amount of time, usually days, but eventually enters a hung state. When hung the CPU load gradually spikes on the machine and new web server requests are unresponsive.
Error logs typically contain lots of these: Wed Jan 28 16:06:58.667188 2015] [mpm_event:error] [pid 25336:tid 1] AH00485: scoreboard is full, not at MaxRequestWorkers I have done a lot of web research on this top and have found many cases where others o=have had the same/similar issue but no real solutions. Seem very close to this bug report: https://issues.apache.org/bugzilla/show_bug.cgi?id=53555 Environment: LDOM (VM) SunOS myhostname 5.10 Generic_118833-36 sun4v sparc SUNW,Sun-Fire-T200 8G RAM http Conf: StartServers 8 MinSpareServers Not set MaxSpareServers Not set ServerLimit 256 MaxRequestWorkers 100 MaxConnectionsPerChild 1000 KeepAlive On TimeOut 3000 MaxKeepAliveRequests 50 KeepAliveTimeout 2 Current non-hung Score Board: Server Version: Apache/2.4.10 (Unix) Server MPM: event Server Built: Oct 30 2014 16:29:03 Current Time: Wednesday, 28-Jan-2015 10:59:39 PST Restart Time: Wednesday, 28-Jan-2015 09:49:21 PST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 1 hour 10 minutes 17 seconds Server load: 0.60 0.46 0.41 Total accesses: 1134 - Total Traffic: 2.2 GB CPU Usage: u9.07 s16.94 cu609.51 cs69.31 - 16.7% CPU load .269 requests/sec - 0.5 MB/second - 2.0 MB/request 1 requests currently being processed, 99 idle workers PID Connections Threads Async connections total accepting busy idle writing keep-alive closing 25337 0 yes 1 24 0 0 0 25338 1 yes 0 25 1 0 0 25339 1 yes 0 25 0 0 1 25340 1 yes 0 25 0 0 1 Sum 3 1 99 1 0 2 Any thoughts/comments on http conf tuning, OS patches, apache bug fixes appreciated. This is a production server, so you can imagine, having it go down at random times (usually when I am asleep) is not fun! Thanks. MJ