VPC flow logs difference with VPC traffic mirroring

VPC Flow Logs is a feature that enables you to capture information about the IP traffic going to and from network interfaces in your VPC. Flow log data is collected outside of the path of your network traffic, and therefore does not affect network throughput or latency.

Traffic Mirroring is an Amazon VPC feature that you can use to copy network traffic from an elastic network interface of type interface. You can then send the traffic to out-of-band security and monitoring appliances for:

• Content inspection
• Threat monitoring
• Troubleshooting

So the logs are just that. Logs about your IP Traffic. Mirroring streams a copy of the network traffic say to an EC2 or Appliance for packet inspection