> -----Original Message----- > From: Evan Klitzke [mailto:eklitzke.lists@xxxxxxxxx] > Sent: Tuesday, February 06, 2007 1:21 AM > To: users@xxxxxxxxxxxxxxxx > Subject: Troubleshooting Tips? > > Hi everyone, > > I am a junior sysadmin (well, intern actually) at a company using > Apache. Right now I am tasked with migrating one of our servers to a > newer machine, and this involved doing more work with Apache > than I have > done previously. I encountered a problem where turning on > mod_perl would > cause Apache to run _really_ slowly (as in taking a minute to return a > small plain HTML page). In this case, I was sort of at a loss > on how to > figure out what was causing the problem. The access and error logs > in /var/log/apache2 weren't showing anything helpful. The man page > indicated that I might be able to get some debugging output > using the -X > option and starting apache at the command line, but I didn't get any > output (probably apache didn't consider anything that was going on > seriously amiss). Since this is something that will come up in the > future again I'm sure, I'm wondering: what is the best way to > troubleshoot Apache problems? Is there a way to turn on really verbose > logging, or to otherwise figure out what the heck is going on when > Apache spends 2-3 minutes just starting itself? I'm as bit confused - is apache slow in starting, or serving once started, or both? General tips: slow operation can be caused by using hostnames instead of IPs in VirtualHost tags etc. This causes apache to rely on DNS at startup (http://httpd.apache.org/docs/2.2/dns-caveats.html). Other issues are network latency (eg, content on NFS) and avoiding sendfile (http://httpd.apache.org/docs/2.2/mod/core.html#enablesendfile). > This is especially > pertinent when Apache isn't actually encountering errors, it is just > running an order of magnitude more slowly than it ought to > be. I realize > there's strace, but using it on something as big and complex as Apache > is somewhat daunting. Maybe - but it might be worth it.. start httpd with the -X option under strace/truss, eg: strace httpd -X -f /path/to/config and sew where it is "waiting"... Rgds, Owen Boyle Disclaimer: Any disclaimer attached to this message may be ignored. > > Thanks a lot! > Evan Klitzke > > > --------------------------------------------------------------------- > 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 > This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. No confidentiality or privilege is waived or lost by any mistransmission. If you receive this message in error, please notify the sender urgently and then immediately delete the message and any copies of it from your system. Please also immediately destroy any hardcopies of the message. You must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message if you are not the intended recipient. The sender's company reserves the right to monitor all e-mail communications through their networks. Any views expressed in this message are those of the individual sender, except where the message states otherwise and the sender is authorised to state them to be the views of the sender's company. --------------------------------------------------------------------- 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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