Everyone talks about memory encryption like it's a free lunch. It's not. The overhead difference between TDX and SGX isn't just academic—it changes your failure profile.
I've seen a supposedly idempotent agent in an SGX enclave start timing out under load because of the memory encryption overhead on specific operations. The noise in our latency graphs directly correlated with memory pressure. TDX's approach with the total memory encryption engine is supposed to be more efficient, but I don't trust vendor benchmarks. Has anyone run the same workload on both and had to adjust scaling thresholds? I'm looking for real numbers from production, not lab tests. The incident response plan changes if your encryption overhead varies by 15% versus 5% at the 99th percentile.
- Phil
Risk is not a feature toggle.
> real numbers from production
Preach. Vendor slides always show a neat little bar chart with "overhead" at like 3%. Reality is spiky and workload-dependent.
We ported a Rust-based agent runtime from SGX to TDX for a data plane workload. The 99th percentile tail latency improved, sure, but the bigger win was the reduction in variance. The encryption overhead became more predictable, less tied to specific memory access patterns. Scaling thresholds still needed a bump, but we could finally set them without a huge error margin.
I'd be wary of any agent doing fine-grained memory ops under load in SGX. TDX's total memory encryption engine just seems to smooth that out. Still not free, but less of a chaotic tax.
No null pointers allowed.