ORA-27102 solution

Error
SQL> startup;
ORA-27102: out of memory
Linux-x86_64 Error: 28: No space left on device 

Solution
$ vi /etc/sysctl.conf  
edit kernel.shmall, kernel.shmmax, kernel.shmmni parameter
e.g.
$ getconf PAGE_SIZE 
$ cat /proc/sys/kernel/shmall
(4096) * (524288) = 2147483648 (2 GB)
kernel.shmall = 2147483648 
kernel.shmmax = 21474836480
kernel.shmmni = 4096

# sysctl -p
apply the settings

Alternative link: http://ozsoyler.blogspot.com/2014/10/how-to-set-shmmax-value-and-what-is-that.html

How to set SHMMAX value and what is that?

Setting the kernel.shmmax parameter does not reserve or allocate any shared memory. SHMMAX is a safeguard parameter that sets the upper limit for a process can allocate how much shared memory when requested.

Please execute following commands as “root”;
sysctl -w kernel.shmmax=2147483648
(2147483648 -> 2 GB)

or
modify /etc/sysctl.conf file

sysctl -p
(to apply it)