Posts Tagged ‘Oracle Linux’

SWAP size Adding While installing a Oracle Database 19c on Oracle Linux

January 30th, 2022, posted in Oracle, Solaris
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SWAP Size Adding  size while installing a Oracle Database 19c on Oracle Linux

Below is the error message I received while I was trying to install Oracle Database 19c on Oracle Linux 7.

PRVF-7573 : Sufficient swap size is not available on node

As per my error on the installer screen I needed 16GB of SWAP space where as my system has just 4GB. So I need to add a swap file for the installation to continue. 

Below steps will outline the steps for the same.

dd if=/dev/sdb of=/tmp/swap01 bs=1K count=16M
chmod 600 /tmp/swap01
mkswap /tmp/swap01
swapon /tmp/swap01

Make sure the bs (*) count is equal to your required SWAP space. Also, the /dev/sdb has enough storage as needed

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Shared Memory Tuning: Startup database – ORA-27102: out of memory Linux-X86_64 Error: 28: No space left on device

May 22nd, 2018, posted in Linux OS, Oracle Queries
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SQL> startup
ORA-27102: out of memory
Linux-x86_64 Error: 28: No space left on device
I have used RHEL X86_64 + memory (32GB) and setted sga_max_size=20G + sga_target=20G and …
$ cat /proc/sys/kernel/shmmax
26843545600
What wrong with my kernel tuning… So, I checked metalink (301830.1) and some recommend from RHEL
They told; set SHMALL to the total amount of physical RAM divided by page size.

SHMALL =>Total amount of shared memory available (bytes or pages)

then:
Check Page Size:
$ getconf PAGE_SIZE
4096
Determine the system wide maximum number of shared memory pages:
$ cat /proc/sys/kernel/shmall
2097152
My system 64bits with memory 32GB, then 1024 * 1024 * 1024 * 32 / 4096 = 8388608
So, change kernel.shmall = 8388608
$ su - root
# echo 8388608 > /proc/sys/kernel/shmall
Or modify /etc/sysctl.conf file:
kernel.shmall=8388608
and
# sysctl -p
After changed… check and startup database again:
$ cat /proc/sys/kernel/shmall
8388608
 
SQL> startup

.

.

.

--- NO ERROR ---
From this idea with memory 32GB
mem=$(free|grep Mem|awk '{print$2}')
totmem=$(echo "$mem*1024"|bc)
huge=$(grep Hugepagesize /proc/meminfo|awk '{print $2}')
max=$(echo "$totmem*75/100"|bc)
all=$(echo "$max/$huge"|bc)
echo "kernel.shmmax = $max"
echo "kernel.shmall = $all"
Result:
kernel.shmmax = 25213120512, kernel.shmall = 12311094
However, This case “ORA-27102: out of memory Linux-X86_64 Error: 28: No space left on device” , solved by set SHMALL = MemTotal(byte)/PAGE_SIZE
and …
I hope to hear your idea about kernel tuning with Oracle Database.
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