Initial Benchmarks Of The Spectre "SWAPGS" Mitigation Performance Impact

The Sockperf socket benchmark was one of the workloads we've seen affected by the other vulnerabilities so was included with this testing. Indeed, the socket throughput performance took a 5% hit as a result of the SWAPGS mitigations alone, not counting the hits from the other mitigations to date. The socket latency was ticking up just slightly higher.

With various Java benchmarks, the SWAPGS mitigations didn't have any real impact or less than 1%.

The synthetic Coremark CPU benchmark did see a ~2% hit from the SWAPGS mitigations.