+
+RUNNING THIS SERVER ON LINUX
+
+If you run Linux 2.6 or above (or 2.4 with appropriate patches), ircu
+can use the epoll family of system calls for much more efficient
+checks of which connections are active. Most pre-epoll systems will
+use 100% CPU with 2000 clients; with epoll, a server may use only a
+few percent of CPU with the same load.
+
+To handle that many connections, the ircd must be started with a high
+enough file descriptor resource. Check your distribution's docs on
+how to set the global and per-user limits according to your expected
+load.
+
+RUNNING THIS SERVER ON FREEBSD
+
+When running on FreeBSD, ircu can make use of the kqueue() event engine, which
+results in much improved performance over the old poll()-based method. kqueue
+is included in the more recent 4.x releases of FreeBSD.
+
+In order for ircu to be able to serve many clients simultaneously, you need
+to increase the maximum allowable number of open files in the system. To do
+this, add commands such as the following during your system's boot sequence:
+
+sysctl -w kern.maxfiles=16384
+sysctl -w kern.maxfilesperproc=16384
+
+Unless you will be serving thousands of clients simultaneously, you will not
+need to do the following, unless of course you just can't stand having a
+system that is not optimized to its limits :)
+
+Build a custom kernel: Make your kernel as lean as possible by removing all
+drivers and options you will not need. The following parameters will affect
+performance, they are listed with suggested values only. For more information
+on what they do exactly, see FreeBSD's documentation.
+
+maxusers 2048
+options NMBCLUSTERS=65535
+options ICMP_BANDLIM
+
+Also, you may wish to run the following at system startup (from /etc/rc.local,
+or whichever other method you prefer):
+
+sysctl -w net.inet.tcp.rfc1323=1
+sysctl -w net.inet.tcp.delayed_ack=0
+sysctl -w net.inet.tcp.restrict_rst=1
+sysctl -w kern.ipc.maxsockbuf=2097152
+sysctl -w kern.ipc.somaxconn=2048
+
+Created by Sengaia <sengaia@undernet.org>, July 20 2002.
+
+RUNNING THIS SERVER ON SOLARIS
+
+When running on Solaris, ircu can make use of the /dev/poll event engine, which
+results in much improved performance over the old poll()-based method. Solaris
+versions 8 and 9 include /dev/poll out of the box, for Solaris 7 you will have
+to grab and install Patch-ID 106541-21.
+
+In order to increase the number of clients ircu can handle, add lines such as
+the following to /etc/system:
+
+* set hard limit on file descriptors
+set rlim_fd_max = 16384
+* set soft limit on file descriptors
+set rlim_fd_cur = 8192
+
+For more useful hints see http://www.sean.de/Solaris/soltune.html
+
+Created by Sengaia <sengaia@undernet.org> on July 20, 2002.