My cron issues a nightly 'apachectl graceful'. Once in a while I will find extra Apache processes running on the server, and when I check them via server-status, a number of them show a state of 'G' (gracefully finishing). They remain in that state indefinitely, and will not go away until I issue a start-and-stop or a restart. The 'top' command shows one of these 'G' processes is stuck in kread, with the rest are in lockf, (I believe due to the accept mutex which allows only one process at a time to poll sockets). I built Apache with symbols and attached a debugger to the one in kread state. The stack trace shows the process calling kevent() from the apr_pollset_poll() function in srclib/apr/poll/unix/kqueue.c, which is called from the main loop in child_main(). When I allow the process to continue, the call to kevent() never returns. I will often find this in my error log when the problem occurs: [error] (9)Bad file descriptor: apr_socket_accept: (client socket) I am able to replicate the behavior in Apache 2.2.4 on FreeBSD 6.2. My build configuration is as follows: ./configure \ --with-apr=/usr/local/apr-httpd/ \ --with-apr-util=/usr/local/apr-util-httpd/ \ --prefix=/usr/local/httpd-2.2.4 \ --with-mpm=prefork \ --enable-mods=info In httpd.conf, I add an extra Listen command: Listen 80 Listen 8080 The behavior will not occur without this, because it needs to be polling multiple sockets via kevent(). I also enable server-status by uncommenting the Include line for httpd-info.conf and adding an 'Allow from' line in the file conf/extra/httpd-info.conf. This is not a required step, but allows me to monitor more easily. Then I start Apache and run a series of 'apachectl graceful' commands. Eventually the behavior will occur, but it speeds things up if I run about a dozen of them on one command line, separated by semi-colons. Usually the hung 'G' process will show up within 2-3 minutes by continually repeating in this way. Am I seeing a known race condition in the code for graceful restart? Or maybe a problem in kevent? I would appreciate any light anyone can shed on this topic. Thanks, -- Omar W. Hannet http://www.allez-oop.net/ --------------------------------------------------------------------- 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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