How resolve Error ORA-00845: MEMORY_TARGET not supported on this system

ORA-00845: MEMORY_TARGET not supported on this system

This error happen when system is running out of temporary storage. While starting up the database oracle uses /dev/shm to store temporary files but when it runs out of memory you will get this error MEMORY_TARGET not supported on this system.

In My case:

MEMORY_TARGET=1000M  and /dev/shm  is 584M


[oracle@localhost ~]$
[oracle@localhost ~]$
[oracle@localhost ~]$ sqlplus "/as sysdba"
star
SQL*Plus: Release 11.2.0.4.0 Production on Tue Feb 6 22:14:11 2018

Copyright (c) 1982, 2013, Oracle.  All rights reserved.

tup
Connected to an idle instance.

SQL> ORA-00845: MEMORY_TARGET not supported on this system
SQL> exit
Disconnected
[oracle@localhost ~]$
[oracle@localhost ~]$ df -h
Filesystem                    Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root   26G   24G  1.5G  95% /
tmpfs                         584M   72K  584M   1% /dev/shm
/dev/sda1                     477M   55M  397M  13% /boot
[oracle@localhost ~]$
[oracle@localhost ~]$



[root@localhost ~]#
[root@localhost ~]# df -h
Filesystem                    Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root   26G   24G  1.5G  95% /
tmpfs                         584M   72K  584M   1% /dev/shm
/dev/sda1                     477M   55M  397M  13% /boot
[root@localhost ~]#

To increase the size 


[root@localhost ~]# mount -o remount,size=1G /dev/shm
[root@localhost ~]#

Verify the size

[root@localhost ~]# df -h
Filesystem                    Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root   26G   24G  1.5G  95% /
tmpfs                         1.0G   72K  1.0G   1% /dev/shm
/dev/sda1                     477M   55M  397M  13% /boot
[root@localhost ~]#


To make permanent changes to your file system update your fstab file


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

#
# /etc/fstab
# Created by anaconda on Tue Dec 19 18:20:28 2017
#
# 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/VolGroup-lv_root /                       ext4    defaults        1 1
UUID=a0d50c7a-876c-4d10-ae50-3caf8cbe182a /boot                   ext4    defaults        1 2
/dev/mapper/VolGroup-lv_swap swap                    swap    defaults        0 0
tmpfs                   /dev/shm                tmpfs   defaults        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@localhost ~]#



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

#
# /etc/fstab
# Created by anaconda on Tue Dec 19 18:20:28 2017
#
# 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/VolGroup-lv_root /                       ext4    defaults        1 1
UUID=a0d50c7a-876c-4d10-ae50-3caf8cbe182a /boot                   ext4    defaults        1 2
/dev/mapper/VolGroup-lv_swap swap                    swap    defaults        0 0
tmpfs                   /dev/shm                tmpfs   defaults,size=1G        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@localhost ~]#


Update the new fstab file ,mount -a command to immediate mount all disk defined in /etc/fstab file

root@localhost ~]#
[root@localhost ~]# mount -a
[root@localhost ~]#
[root@localhost ~]#



[oracle@localhost ~]$ sqlplus "/as sysdba"

SQL*Plus: Release 11.2.0.4.0 Production on Tue Feb 6 22:35:35 2018

Copyright (c) 1982, 2013, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area 1043886080 bytes
Fixed Size                  2259840 bytes
Variable Size             654312576 bytes
Database Buffers          381681664 bytes
Redo Buffers                5632000 bytes
Database mounted.
Database opened.
SQL> show parameter target

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
memory_max_target                    big integer 1000M
memory_target                        big integer 1000M
parallel_servers_target              integer     16
pga_aggregate_target                 big integer 0
sga_target                           big integer 0
SQL>



verify /dev/shm after reboot OS:

[oracle@localhost ~]$
[oracle@localhost ~]$ df -h
Filesystem                    Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root   26G   24G  1.5G  95% /
tmpfs                         1.0G     0  1.0G   0% /dev/shm
/dev/sda1                     477M   55M  397M  13% /boot
[oracle@localhost ~]$