[Solved] ORA-00845: MEMORY_TARGET not supported on this system

Error: 
SQL> startup
ORA-00845: MEMORY_TARGET not supported on this system
SQL>

Solution: Set the parameter value in file $ORACLE_HOME/dbs/init<dbname>.ora, Parameter value must satisfied below formula:
MEMORY_TARGET = SGA_TARGET + PGA_AGGREGATE_TARGET

Example:
crd.__pga_aggregate_target=260046848
crd.__sga_target=381681664
*.memory_target=639631360

Now increase the size of tmpfs File system in Linux: follow below steps:

[oracle@ole1 dbs]$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_ole1-lv_root
                       18G   12G  5.3G  68% /
tmpfs                 764M  124K  763M   1% /dev/shm
/dev/sda1             485M   53M  407M  12% /boot
.host:/               238G  230G  7.9G  97% /mnt/hgfs

[root@ole1 ~]# cat /etc/fstab

#
# /etc/fstab
# Created by anaconda on Fri May 30 14:47:40 2014
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/vg_ole1-lv_root /                       ext4    defaults        1 1
UUID=b7e7d6ba-7a0d-4440-bff1-fc9e53333bd0 /boot                   ext4    defaults        1 2
/dev/mapper/vg_ole1-lv_swap swap                    swap    defaults        0 0
tmpfs                   /dev/shm                tmpfs   size=2g       0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
[root@ole1 ~]#

[root@ole1 ~]# mount -o remount tmpfs
[root@ole1 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_ole1-lv_root
                       18G   12G  5.3G  68% /
tmpfs                 2.0G  124K  2.0G   1% /dev/shm
/dev/sda1             485M   53M  407M  12% /boot
.host:/               238G  230G  7.9G  97% /mnt/hgfs
[root@ole1 ~]#

SQL> startup
ORACLE instance started.

Total System Global Area 1255473152 bytes
Fixed Size    1336232 bytes
Variable Size  671091800 bytes
Database Buffers  570425344 bytes
Redo Buffers   12619776 bytes
Database mounted.
Database opened.
SQL>

SQL> show parameter memory

NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
hi_shared_memory_address     integer 0
memory_max_target     big integer 1200M
memory_target     big integer 1200M
shared_memory_address     integer 0
SQL>