> -----Original Message----- > From: ocfs2-users-boun...@oss.oracle.com [mailto:ocfs2-users- > boun...@oss.oracle.com] On Behalf Of David Johle > Sent: 01/28/2009 10:12 > To: jmose...@corp.xanadoo.com > Cc: ocfs2-users@oss.oracle.com > Subject: Re: [Ocfs2-users] ocfs2 hangs during webserver usage > > At 06:32 PM 1/27/2009, jmose...@corp.xanadoo.com wrote: > >As others have indicated, I don't think that's going to work very > well. > >You've got two different nodes trying to write to the same file > constantly. > >I would keep each server's log on a locally mounted file system, or > simply > >keep the logs on the OCFS2 filesystem, but have each node write to > >different log files. > > > >Yeah, that makes parsing access_logs slightly more of a problem for > >producing hit reports, etc, but I think you'll notice performance > improve. > > > Yes, parsing logs is just one good reason for having unified log > files -- one of the motivations for using OCFS2 even. If our > statistics program can handle multiple files, then at least having > them in a shared directory would be useful. > > Another major area this would affect is web site issue > troubleshooting which outputs to log files (not the access logs but > others). I can only imagine the complexity of having to deal with > locating specific logging information for a site user who is having > trouble by going to 5 different nodes to dig through locally stored > log files. Or worse yet, trying to correlate actions of multiple > users who are each hitting different nodes! > > On that note, these other logs are written to by our aplications > running under Tomcat. I really am not seeing any similar lags for > those processes, only from apache. The only big difference I can see > between them is the I/O pattern -- apache is usually 1 line per > request as they are serviced, java web apps are more bursts of > numerous lines, but not every request. There is still a non-trivial > amount of logging happening for these java apps though, so I am > surprised. In fact, Tomcat itself is configured to log each request > with the processing time (used to produce user response time > statistics), but those shared logs don't seem to be a point of > contention like the apache access logs. > > For informational purposes, here are some line counts for logs on our > main web site yesterday: > 1577860 access log > 1361 error log > 4887437 web app log > 340164 processing time log > 6806822 total > > So only about 20% of the requests are handled by Tomcat. The web app > log actually writes 3x as many lines, but overall it's less data > (373M vs. 428M) and fewer actual write operations. This could > explain why it is not/less prone to these write delays.
1.5 million hits for access log is not that much and you should be able to use separate files and then combine it into 1 before processing. The tools are out there for that. Another option is to send Apache logs to syslog, which means you have now 1 process receiving and writing the logfiles. _______________________________________________ Ocfs2-users mailing list Ocfs2-users@oss.oracle.com http://oss.oracle.com/mailman/listinfo/ocfs2-users
