


Method - Increase the maximum number of open file descriptors under Linux
I encountered an error when installing Oracle Grid Infrastructure to check constraints. It basically means that the maximum number of file descriptors that can be opened is 1024, and the requirement is 65536.
So execute ulimit -a under the girl user, and the maximum number of files that can be opened is 1024, which is the default value; execute ulimit -n 65536 and no modification is allowed. Go to root and execute ulimit -n 65536, and execute ulimit - a is displayed as 65536, and it is still 1024 when executed under the grid user. At that time, I thought of using sudo to execute, granting all permissions to the gird user, and executing ulimit -n 65536 still reported an error.
Later I remembered that in the configuration /etc/profile file, there is a ulimit -n 65536 command for oracle, as follows:
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
After adding the grid user, source /etc/profile
if [ $USER = "oracle" ] || [ $USER = "grid" ] ; then
if [ $SHELL = "/bin/ksh" ]; then
ulimit -p 16384
ulimit -n 65536
else
ulimit -u 16384 -n 65536
fi
umask 022
fi
Executing ulimit -a on the grid is still 1024. Later, after checking the installation steps, I found that I forgot to add the grid user in /etc/security/limits. Just add the following:
grid soft nproc 2047
grid hard nproc 16384
grid soft nofile 1024
grid hard nofile 65536
It seems to be a scope problem, increase the file descriptor.
The above is the detailed content of Method - Increase the maximum number of open file descriptors under Linux. For more information, please follow other related articles on the PHP Chinese website!

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