few words about shared memory
Shared memory allows processes to access common structures and data by placing them in shared memory segments. It is the fastest form of inter-process communication available since no kernel involvement occurs when data is passed between the processes. In fact, data does not need to be copied between the processes.
we notice that value in redhat machines is huge as the following
cat /proc/sys/kernel/shmmax 17446744003692774391 sysctl -a | grep kernel.shmmax kernel.shmmax = 17446744003692774391
when I calculated to Giga its - 16248546544.17632
is it logical? , do we miss something here
machines are with 64G and 16 CPU and are use in hadoop cluster