ORA-00845: MEMORY_TARGET not supported on this system

Today  We can discuss about the major oracle error , when  we start the oracle database by issuing "Startup " commands  its throw error

ORA-00845: MEMORY_TARGET not supported on this system

 from the leaning stage its big hectic of us ,Here i Mentioned  two methods to solve this error

Method 1:
      
 SQL> startup
 ORA-00845: MEMORY_TARGET not supported on this system
SQL> create pfile from spfile;
file has been created 

we need the pfile to solve these error ,so let's create the pfile (The default file has been created on "$ORACLE_HOME/dbs/"  location initdbname.ora)

SQL> shut immediate

because we ll up database by using  pfile so we must  shut database 

SQL>!
oracle@host.] cd $ORACLE_HOME/dbs
oracle@host dbs]ls 
spfileram.ora initram.ora

now i m going to edit this pfile 
 oracle@host dbs>vi initram.ora

now the parameters of pfile will be dispalyed here

we should replace instead of MEMORY_TARGET into SGA_TARGET

then press ESC
:wq 
The File has been saved and then start your db using  pfile

SQL>startup pfile='/u01/app/oracle/product/11.2.0.3/db_1/dbs/initram.ora'

Now the database is started 

METHOD 2:

SQL> !

[oracle@host.] df -h

this command ll display the space in linux like below

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_oracleem-lv_root
                       93G   19G   69G  22% /
tmpfs                  504M  76K  504M   1% /dev/shm
/dev/sda1             485M   99M  362M  22% /boot

now  we have login on root user 

 [oracle@host.]su - root 

password:              (enter your root user password)

[root@host]#    mount -o remount,size=3G /dev/shm 

 [root@host]# df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_oracleem-lv_root
                       93G   19G   69G  22% /
tmpfs                  3G    1007M  2.1G 33% /dev/shm
/dev/sda1             485M   99M  362M  22% /boot

 [root@host]# cat /etc/fstab

Now try  to  start the db using  startup command the error ll be rectified