Increase SGA on 12c

Hello,

Plan to increase DB memory but i want to confirm about /dev/shm. Any related with the db memory configuration

OS : Red hat linux 64bit

DB : 12c Release 1

$ df -kh

Filesystem               Size Used Avail Use% Mounted on

devtmpfs                16G   0  16G  0% /dev

tmpfs                  16G 7.2G 8.5G 46% /dev/shm

tmpfs                  16G 1.6G  15G 11% /run

tmpfs                  16G   0  16G  0% /sys/fs/cgroup

2.0 Current db memory setting

show parameter target

NAME                 TYPE    VALUE

------------------------------------ ----------- ------------------------------

archive_lag_target          integer   0

db_big_table_cache_percent_target  string   0

db_flashback_retention_target    integer   1440

fast_start_io_target         integer   0

fast_start_mttr_target        integer   0

memory_max_target          big integer 12G