On Mon, Jun 07, 2004 at 11:21:25AM +0200, Bert Vanderbauwhede wrote:
The only thing I can conclude, is that the problem is caused by requests that somehow lock up Zope. These requests come from one or more users at the university.
(snip) Just a guess, but maybe there are some local user(s) who are infected with worms / virii that are DOSing your Zope? I'd look through your Zope access log and see if it's only the number of requests that are a problem, or the I've seen on some of my sites that extremely large numbers of requests to non-existent pages can effectively DOS zope. But I've never found a solution other than waiting for the storm to subside. I'd like to do some research on this "if I get time"... Another guess: Do you use ZEO? Can you see if there were several overlapping requests for downloading large files? I found that this slowed zope so much that no more requests completed until one or several of the large file requests finally succeeded. I noticed in the ZEO server log that there were a bunch of cache flip messages in quick succession. My interpretation is that the ZEO cache is basically overloaded to the point of being useless, and most/all requests are waiting on the very busy ZEO connection. Things got better when I drastically increased the size of the ZEO client cache so that no single download could trigger a cache flip. -- Paul Winkler http://www.slinkp.com