General
====================
Increase Oracle memory
Increase /dev/shm
====================
Try to increase Oracle memory
====================
Start Point:
SQL>
COL value for A30
SELECT name, value FROM V$PARAMETER WHERE name like 'memory%';
NAME VALUE
------------------------------ ------------------------------
memory_target 1073741824
memory_max_target 1073741824
Linux server has 40Gb memory
SQL> !free -m
total used free shared buffers cached
Mem: 38154 1628 36526 672 31 1040
-/+ buffers/cache: 556 37598
Swap: 9215 0 9215
Let increase MEMORY_MAX_TARGET to 30Gb:
ALTER SYSTEM SET MEMORY_MAX_TARGET=30000M scope=spfile;
SQL> SHUTDOWN IMMEDIATE;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> STARTUP;
ORA-01078: failure in processing system parameters
ORA-00838: Specified value of MEMORY_TARGET is too small, needs to be at least 1408M
SQL> ALTER SYSTEM SET MEMORY_TARGET=3000M scope=spfile;
ALTER SYSTEM SET MEMORY_TARGET=3000M scope=spfile
*
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 0
Session ID: 866 Serial number: 23
SQL> create pfile='/software/oracle/admin/igt/pfile/pfile_20201201_initigt.ora' from spfile='/software/oracle/admin/igt/pfile/spfileigt.ora';
File created.
Edit manually file pfile.
set MEMORY_TARGET to be 2000M
*.memory_target=2147483648
SQL> startup pfile='/software/oracle/admin/igt/pfile/pfile_20201201_initigt.ora'
ORA-00845: MEMORY_TARGET not supported on this system
Check Alert Log for more details:
Tue Dec 01 09:35:05 2020
Cannot set memory_target (1073741824) < min sga_target (1476395008) + pga_aggregate_target (0)
Starting ORACLE instance (normal)
WARNING: You are trying to use the MEMORY_TARGET feature.
This feature requires the /dev/shm file system to be mounted for at least 31474057216 bytes.
/dev/shm is either not mounted or is mounted with available space less than this size.
Please fix this so that MEMORY_TARGET can work as expected.
Current available is 4294967296 and used is 0 bytes.
Ensure that the mount point is /dev/shm for this directory.
memory_target needs larger /dev/shm
Checking the Linux server
SQL> !df -h /dev/shm
Filesystem Size Used Avail Use% Mounted on
tmpfs 4.0G 0 4.0G 0% /dev/shm
/dev/shm cannot support memory more than 4G memory
Need to change max_memory_target and memory_target to 2Gb for now
*.memory_max_target=2000M
*.memory_target=2000M
ORACLE instance started.
Total System Global Area 2087780352 bytes
Fixed Size 2254824 bytes
Variable Size 1577060376 bytes
Database Buffers 503316480 bytes
Redo Buffers 5148672 bytes
Database mounted.
Database opened.
Re-Create spfile from pfile
SQL> create spfile='/software/oracle/admin/igt/pfile/spfileigt.ora' from pfile='/software/oracle/admin/igt/pfile/pfile_20201201_initigt.ora';
File created.
Increase /dev/shm from current 4Gb to 30Gb, out of server total 40Gb
oracle@avilab-1-aps-01:~>% df -hP
Filesystem Size Used Avail Use% Mounted on
tmpfs 4.0G 331M 3.7G 9% /dev/shm
Step 1:
vi /etc/fstab
Step 2:
Change size for /dev/shm to 30G
change from :
tmpfs /dev/shm tmpfs size=4g,nodev,nosuid,noexec 0 0
to:
tmpfs /dev/shm tmpfs size=30g,nodev,nosuid,noexec 0 0
stop oracle!!
Step 3:
Remount /dev/shm filesystem
mount -o remount /dev/shm
Step 4:
Check status:
df -hP | grep shm
Filesystem Size Used Avail Use% Mounted on
tmpfs 30G 700M 30G 3% /dev/shm
start oracle
ALTER SYSTEM SET MEMORY_MAX_TARGET=8192M scope=spfile;
SQL> ALTER SYSTEM SET MEMORY_MAX_TARGET=4000M scope=spfile;
System altered.
SQL> ALTER SYSTEM SET MEMORY_TARGET=4000M scope=spfile;
System altered.
SQL> SHUTDOWN IMMEDIATE;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> STARTUP;
ORACLE instance started.
Total System Global Area 3.1334E+10 bytes
Fixed Size 2268632 bytes
Variable Size 3.0803E+10 bytes
Database Buffers 469762048 bytes
Redo Buffers 58535936 bytes
Database mounted.
Database opened.
>% df -hP
Filesystem Size Used Avail Use% Mounted on
tmpfs 30G 1.2G 29G 4% /dev/shm
