Hi Rick! 2016-05-31 15:57 GMT+02:00 Houser, Rick <rick.hou...@jackson.com>:
> I have to deal with mod_cluster, and it is extremely memory hungry (in the > GB range per process). As mitigation, I’m trying to get down to a single > apache worker process per host when we aren’t under heavy load. That would > save me about 6GB per host. > > > > We have several hosts running the exact same thing behind a load balancer > and I’ve never seen a crash, so I’m not concerned with running a single > instance. Running 4 20 thread instances is almost 4 times the memory of > this one instance, for example. > > > > > > This is the relevant portion of the configuration: > > > > LoadModule mpm_event_module modules/mod_mpm_event.so > > ServerLimit 8 > > StartServers 1 > > ThreadLimit 80 > > ThreadsPerChild 80 > > MaxRequestWorkers 640 > > MaxSpareThreads 120 > > MinSpareThreads 8 > > > > > > > > The top of mod-Status: > > > > Apache Server Status for HOSTNAME (via 10.X.X.X) > > Server Version: CUSTOMSTRING/2.4.18 (Unix) OpenSSL/1.0.1e-fips > mod_cluster/1.3.1.Final > > Server MPM: event > > Server Built: Dec 16 2015 16:07:29 > > ________________________________________ > > Current Time: Tuesday, 17-May-2016 14:37:00 EDT > > Restart Time: Monday, 02-May-2016 09:36:16 EDT > > Parent Server Config. Generation: 10 > > Parent Server MPM Generation: 9 > > Server uptime: 15 days 5 hours 44 seconds > > Server load: 0.72 0.75 0.89 > > Total accesses: 39007867 - Total Traffic: 1.7 GB > > CPU Usage: u2533.2 s168.49 cu0 cs0 - .206% CPU load > > 29.7 requests/sec - 1364 B/second - 45 B/request > > 5 requests currently being processed, 155 idle workers > > PID Connections Threads Async connections > > total accepting busy idle > writing keep-alive closing > > 11397 35 yes 2 78 > 0 33 0 > > 29323 26 yes 3 77 > 0 23 0 > > Sum 61 5 155 > 0 56 0 > > ................................................................ > > ................________________________________________________ > > _______W____W___________________................................ > > ................................................____________W___ > > ______W__________________________________W______________________ > > ................................................................ > > ................................................................ > > ................................................................ > > ................................................................ > > ................................................................ > > > > > > The idle threads here usually stays around the mid 150s. These particular > workers were started about 40 minutes apart, but I have the similar pattern > showing in other regions with similar start times and the same workers > being up for over a month. > > > > Given the MaxSpareThreads 120, I would expect this to drop the second > worker fairly quickly and work as described ( > https://httpd.apache.org/docs/2.4/mod/mpm_common.html#maxsparethreads). > But, that’s not happening and I'm stuck with two processes handling the > load. It's acting almost as if there is a "ServerMin 2" directive > hard-coded or something. > > > > This certainly looks like a bug (whether in the documentation or the code > itself). Any suggestions on how to get this to work before I submit a bug > ticket? > > > IIRC we had a similar issue earlier on in this email list: https://www.mail-archive.com/users@httpd.apache.org/msg60181.html Afaik the fix has not been ported to the 2.4.x branch yet.. If this is what you are experiencing, we'll follow up with the devs to check what is the status of the backport proposal. Let me know! Luca
