Hello List, I have a FreeBSD 5.5 (amd64) server with the following: Apache/2.0.61 (FreeBSD) mod_ssl/2.0.53 OpenSSL/0.9.7e-p1 PHP/4.4.4 with Suhosin-Patch mod_apreq2-20051231/2.6.0 mod_perl/2.0.3 Perl/v5.8.6 Background: The server was recently updated to FreeBSD 5.5 from 5.3, which had run for a couple of years without interruption. I'm not especially convinced the issue I'm having is related to this upgrade, but it's the most significant change in some time, so it's worth mentioning. Apache is configured with KeepAlive on, as this box provides a number of other services, but I noticed last week that the majority of the requests (specifically those being handled by HTML::Mason via mod_perl) were not sending a Content-Length header, and thus the KeepAlive settings were largely useless. I added this header to the mod_perl output, and began tuning apache to maximize performance. I got, for us, quite acceptable results using the following: <IfModule prefork.c> StartServers 5 MinSpareServers 5 MaxSpareServers 10 MaxClients 200 MaxRequestsPerChild 0 </IfModule> The problem: After a few days the server became unstable. Twice the server was out of swap space and had to be rebooted. While attempting to solve this problem, I came to understand that the webserver seemed responsible; for as-yet unknown reason, the box will suddenly lock up, and if I do not kill httpd within 5 or 10 seconds the server will become completely unresponsive and need to be rebooted. If left alone, swap space will be consumed and the kernel will begin killing off httpd processes, but not fast enough. By altering the apache config to the following, I am able to avoid the hang: <IfModule prefork.c> StartServers 5 MinSpareServers 5 MaxSpareServers 5 MaxClients 40 MaxRequestsPerChild 0 </IfModule> But naturally this provides less than optimal performance. Other things I tried, without impact: -- setting KeepAlive off -- disabling all vhosts -- disabling mod_perl2 -- disabling mod_php -- running httpd -X -- tweaking/disabling resource limits via Apache2::Resource -- recompiling httpd -- recompiling mod_perl2 -- recompiling & reinstalling the freebsd userland The server has 1gb of ram, 4gb of swap (I recently doubled it in an attempt to give me more time to diagnose the problem when it occurs -- didn't help, as the lock-up occurs long before swap is consumed), and in the moments before the hang, shows no particular level of activity -- swap usage is around 100mb, load is very low (1.5 - 2.0 on a dual-proc system). There doesn't seem to be any correlation to specific requests or request types, whether static, cgi, mod_perl or php. There are no errors in the server logs prior to the lock up ( although once, and only once, i saw "httpd in free(): error: page is already free" ). I'm hoping someone here can make some suggestions on how to troubleshoot the problem further, because I'm kind of at a loss. I have not (yet) posted this to the mod_perl list or freebsd-users, though I would be happy to do so if it's thought the problem might lie within those realms. Thanks! Greg --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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