Depending on the requirement, you must set the Linux kernel parameters before Oracle database installation.
Configuring Linux Kernel Parameters for Oracle
Login as root user and add the following entries to /etc/sysctl.conf file
kernel.shmmax = Total Memory or it should be large enough to hold the entire SGA.
kernel.shmall = SHMMAX/ pagesize
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 6815744
net.ipv4.ip_local_port_range = 9000 65500
net.core.rmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048576
Note: To check the pagesize, run the following command at the command prompt
$ getconf PAGE_SIZE.
Execute the following command to make the changes take effect:
/sbin/sysctl –p
Reboot the server and check if all the above settings have taken effect.
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
The ulimit command sets user process resource limits for oracle, rocfm users, as defined in the /etc/security/limits.conf file. This file should contain these limits:
* soft fsize unlimited
* hard fsize unlimited
* soft cpu time unlimited
* hard cpu time unlimited
* soft data unlimited
* hard data unlimited
* soft max memory size unlimited
* hard max memory size unlimited
* soft stack 131072
* hard stack 131072
* soft nofile 65535
* hard nofile 65535
* soft virtual memory unlimited
* hard virtual memory unlimited
* soft nproc 29995
* hard nproc 29995
* soft thread unlimited
* hard thread unlimited
* soft core unlimited
* hard core unlimited
Note: Server needs to be rebooted after setting kernel parameters