One of our customer need to decreased server RAM from 128Gb to 32 Gb.

After closing database, We rebooted server. While server trying to open it gave below error message:

Here is the solution for this error:

  1. Check below files for hugepages config
cat /etc/sysctl.conf |grep -i huge
vm.nr_hugepages = 38903

cat /etc/sysctl.d/99-initial-sysctl.conf |grep -i huge vm.nr_hugepages = 5000
cat /etc/sysctl.d/99-oracle-rdbms-server-12cR1-preinstall-sysctl.conf |grep -i huge vm.nr_hugepages = 5000

Found these miss-configuration from the data collected

  1. Update/Edit files and set the kernel parameter value “same” everywhere.
  2. Reboot server

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