Normally in Linux (see Oracle pdf concerning installation on Ulix/Linux):

http://www.oracle.com/technology/pub/articles/smiley_10gdb_install.html?_template=/ocom/technology/content/print


Required package versions (or later):
"      binutils-2.15.92.0.2-10.EL4
"      compat-db-4.1.25-9
"      control-center-2.8.0-12
"      gcc-3.4.3-9.EL4
"      gcc-c++-3.4.3-9.EL4
"      glibc-2.3.4-2
"      glibc-common-2.3.4-2
"      gnome-libs-1.4.1.2.90-44.1
"      libstdc++-3.4.3-9.EL4
"      libstdc++-devel-3.4.3-9.EL4
"      make-3.80-5
"      pdksh-5.2.14-30
"      sysstat-5.0.5-1
"      xscreensaver-4.18-5.rhel4.2
"      libaio-0.3.96
"      openmotif21-2.1.30-11.RHEL4.2  (Required only to install Oracle demos.  Installation of Oracle demos is not covered by this guide.)

Configuring the Linux Kernel Parameters
The Linux kernel is a wonderful thing. Unlike most other *NIX systems, Linux allows modification of most kernel parameters while the system is up and running. There's no need to reboot the system after making kernel parameter changes. Oracle Database 10g Release 2 requires the kernel parameter settings shown below. The values given are minimums, so if your system uses a larger value, don't change it.
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default=262144
net.core.wmem_default=262144
net.core.rmem_max=262144
net.core.wmem_max=262144
If you're following along and have just installed Linux, the kernel parameters will all be at their default values and you can just cut and paste the following commands while logged in as root.
cat >> /etc/sysctl.conf <kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default=262144
net.core.wmem_default=262144
net.core.rmem_max=262144
net.core.wmem_max=262144
EOF
/sbin/sysctl -p

Ex:
# cat >> /etc/sysctl.conf <> kernel.shmall = 2097152
> kernel.shmmax = 536870912
> kernel.shmmni = 4096
> kernel.sem = 250 32000 100 128
> fs.file-max = 65536
> net.ipv4.ip_local_port_range = 1024 65000
> EOF
# /sbin/sysctl -p
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000

net.core.rmem_default = 262144
net.core.wmem_default = 262144
net.core.rmem_max = 262144
net.core.wmem_max = 262144
Run the following commands as root to verify your settings:
/sbin/sysctl -a | grep shm
/sbin/sysctl -a | grep sem
/sbin/sysctl -a | grep file-max
/sbin/sysctl -a | grep ip_local_port_range
/sbin/sysctl -a | grep rmem_default
/sbin/sysctl -a | grep rmem_max
/sbin/sysctl -a | grep wmem_default
/sbin/sysctl -a | grep wmem_max

Ex:
# /sbin/sysctl -a | grep shm
kernel.shmmni = 4096
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shm-use-bigpages = 0
# /sbin/sysctl -a | grep sem
kernel.sem = 250 32000 100 128
# /sbin/sysctl -a | grep file-max
fs.file-max = 65536
# /sbin/sysctl -a | grep ip_local_port_range
net.ipv4.ip_local_port_range = 1024 65000
# /sbin/sysctl -a | grep rmem_default
net.core.rmem_default = 262144
# /sbin/sysctl -a | grep rmem_max
net.core.rmem_max = 262144
# /sbin/sysctl -a | grep wmem_default
net.core.wmem_default = 262144
# /sbin/sysctl -a | grep wmem_max
net.core.wmem_max = 262144
For Novell SUSE Linux releases, use the following to ensure that the system reads the /etc/sysctl.conf file at boot time:
/sbin/chkconfig boot.sysctl on
Setting Shell Limits for the oracle User
Oracle recommends setting limits on the number of processes and open files each Linux account may use. To make these changes, cut and paste the following commands as root:
cat >> /etc/security/limits.conf <oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
EOF

cat >> /etc/pam.d/login <session required /lib/security/pam_limits.so
EOF
For RHEL4, use the following:
cat >> /etc/profile <if [ \$USER = "oracle" ]; then
 if [ \$SHELL = "/bin/ksh" ]; then
 ulimit -p 16384
 ulimit -n 65536
 else
 ulimit -u 16384 -n 65536
 fi
 umask 022
fi
EOF

cat >> /etc/csh.login <if ( \$USER == "oracle" ) then
 limit maxproc 16384
 limit descriptors 65536
 umask 022
endif