APPLIES TO:Oracle Database Cloud Schema Service - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database - Enterprise Edition - Version 126.96.36.199 and later
Oracle Cloud Infrastructure - Version N/A and later
Oracle Database Backup Service - Version N/A and later
- Database Alert log captures below:
- Network communication issue and High Memory consumption would be observed during this time.
- Server is running with UEK3 kernel
This happens due to less space available for network buffer reservation.
1. On servers with High Physical Memory, the parameter vm.min_free_kbytes should be set in the order of 0.4% of total Physical Memory. This helps in keeping a larger range of defragmented memory pages available for network buffers reducing the probability of a low-buffer-space conditions.
On NUMA Enabled Systems, the value of vm.min_free_kbytes should be multiplied by the number of NUMA nodes since the value is to be split across all the nodes.
2. Additionally, the MTU value should be modified as below
To make the change persistent over reboot add the following line in the file /etc/sysconfig/network-scripts/ifcfg-lo :
Save the file and restart the network service to load the changes