Kshitij Gupta
Kshitij Gupta is a Senior Engineer at AWS Lambda, where he has spent the past eight years building and scaling the VM data plane that supports millions of invocations. During his more than 10 years at AWS, he has focused on building and operating highly scalable systems. He has helped build Lambda's data plane from the ground up, delivering features such as SnapStart. He holds multiple patents in the serverless space and is currently focused on scalable multitenant networking data planes with eBPF.
Session
Running thousands of snapshotted VMs pushes Linux networking to its limits. This talk covers battle-tested strategies balancing performance, isolation, and efficiency across large-scale topologies. We explore Geneve tunneling for scalable overlay networks, eBPF-accelerated networking for line-rate performance, and stateless NAT without connection tracking overhead. Prefix-based iptables/nftables rules scale to thousands of instances, while namespace pooling minimizes snapshot operation costs. We also address RTNL lock contention and its mitigation. Attendees will learn to architect network stacks for snapshotted workloads where VMs are cloned, restored, and migrated while maintaining security and predictable performance.