I sometimes forget what options I need to change to up max open files, and stuff like that. This is a simple page to help me, and hopefully it helps you. To change sysctl options on boot you will have to change the /etc/sysctl.conf, and add whatever options you want to the file. To see your current sysctl options just use sysctl -a like so.
$ sysctl -a
$ vi /etc/sysctl.conf
Here is what you add to max open files, threads, and inodes on your system.
fs.file-max=16384
fs.inode-max = 65536
kernel.threads-max=2048
Here are some sysctl options that I have used before to help the networking on a Linux server. I have never really been able to really see the difference, but some admins swear by them. Well we know some people are crazy. Like windows administrators.
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_syncookies = 1
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
After editing your sysctl.conf file you will have to run the following command to update the machine so the options take effect immediately.
$ /sbin/sysctl -p
Well feel free to add comments, and other helpful hints.