I.4 Ring Buffer Configuration

To be enabled on the KVM flavor and glance image for ring buffer configuration. This improves the network throughput of a VM.

1. Ensure that the ring buffer sizes are set to max on all the ether-net devices on the host machine.
   1. Create /sbin/ifup-local file.

      [root@DSR-Gen10-ol7 ova]# touch /sbin/ifup-local

   2. Change the permission.

      [root@DSR-Gen10-ol7 ova]# chmod +x /sbin/ifup-local

   3. Change file security context.

      [root@DSR-Gen10-ol7 ova]# chcon --reference /sbin/ifup /sbin/ifup-local

      Add the below script to file /sbin/ifup-local:

      #!/bin/bash
      /sbin/ethtool -G eth0 rx 4078 tx 4078
      /sbin/ethtool -G eth1 rx 4078 tx 4078
      /sbin/ethtool -G eth2 rx 4078 tx 4078
      /sbin/ethtool -G eth3 rx 4078 tx 4078

2. Verify that the ring buffer sizes are set to max on all the ether-net devices on the host machine:

   # ethtool -g <ethernet adapter>

   Verify the same for eth1, eth2 and eth3.

3. Restart all ethernet adapter eth0, eth1, eth2,eth3, one by one, by using the following command:

   [root@DSR-Gen10-ol7 ova]# ifdown <ethernet adapter>
   [root@DSR-Gen10-ol7 ova]# ifup <ethernet adapter> 

   Verify again by using Step 2.