I found some info about this on this page: http://www.cs.wisc.edu/~adesmet/linux_scalability.html It looks like you can do it, but it isn't just echoing 1 or 0 to a /proc/ filesystem location. I have not tested it. >>> JAustad at temgweb.com 07/17/03 11:54AM >>> > That's simply untrue, there are many IRC servers out there that handle > thousands of clients running on Linux, and have done so since > the 2.2.x > kernels. I've argued this before on this list. :) With FreeBSD, you just add -DFD_SETSIZE when you compile, and this works. However, with linux, you cannot do this. There is a hard limit of 1024 descriptors in FD_SET(). Apparently, you can't just change it and recompile as it will break a bunch of things. I would assume that these IRC servers are forking multiple copies or using poll() instead of select() (qmail uses select()). If you can get qmail running on linux with a conf-spawn of more than 509, I'd like to see it. I spent weeks trying to get this to work, I tried recompiling the kernel, using ulimit, changing things in /proc, and there is still a hard set limit for FD_SET of 1024. Anyway, if I remember correctly, it's qmail-queue that actually dies when you go over the limit. It communicates with every qmail-send process that's running, and has a file descriptor open for each one, rather than qmail-send opening the descriptor itself. _______________________________________________ TCLUG Mailing List - Minneapolis/St. Paul, Minnesota http://www.mn-linux.org tclug-list at mn-linux.org https://mailman.real-time.com/mailman/listinfo/tclug-list