Async File IO has regressed on Windows #67965
Description
Various async file IO micro benchmarks have regressed on Windows, but System.IO.Tests.Perf_RandomAccess.ReadScatterAsync(fileSize: 104857600, buffersSize: 65536, options: Asynchronous) is the one for which its most obvious (other benchmarks are more noisy):
Looking at the commit diff, #64834 seems to be to blame (cc @kouvel).
Repro:
git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_monthly.py net7.0-preview2 net7.0-preview3 --filter System.IO.Tests.Perf_RandomAccess.ReadScatterAsync
## System.IO.Tests.Perf_RandomAccess.ReadScatterAsync(fileSize: 104857600, buffersSize: 65536, options: Asynchronous)
| Result | Base | Diff | Ratio | Operating System | Bit | Processor Name |
|---|---|---|---|---|---|---|
| Same | 37590691.92 | 35916562.67 | 1.05 | alpine 3.12 | Arm64 | Unknown processor |
| Same | 35082625.33 | 34730510.50 | 1.01 | ubuntu 18.04 | Arm64 | Unknown processor |
| Same | 177006300.00 | 186064200.00 | 0.95 | Windows 10 | Arm64 | Microsoft SQ1 3.0 GHz |
| Slower | 245370200.00 | 274912400.00 | 0.89 | Windows 11 | Arm64 | Microsoft SQ1 3.0 GHz |
| Same | 8429207.03 | 8253338.53 | 1.02 | macOS Monterey 12.3 | Arm64 | Apple M1 Max |
| Same | 95101450.00 | 103159400.00 | 0.92 | Windows 10 | X64 | Intel Xeon CPU E5-1650 v4 3.60GHz |
| Slower | 82646762.50 | 100602725.00 | 0.82 | Windows 11 | X64 | AMD Ryzen Threadripper PRO 3945WX 12-Cores |
| Same | 72943362.50 | 80936137.50 | 0.90 | Windows 11 | X64 | Intel Core i7-8700 CPU 3.20GHz (Coffee Lake) |
| Slower | 70063175.00 | 85975425.00 | 0.81 | Windows 11 | X64 | Intel Core i9-9900T CPU 2.10GHz |
| Slower | 10059315.79 | 11916405.00 | 0.84 | alpine 3.13 | X64 | Intel Core i7-7700 CPU 3.60GHz (Kaby Lake) |
| Same | 26718361.11 | 25572313.94 | 1.04 | centos 7 | X64 | Intel Xeon CPU E5530 2.40GHz |
| Same | 9761970.00 | 10212622.22 | 0.96 | debian 11 | X64 | Intel Core i7-7700 CPU 3.60GHz (Kaby Lake) |
| Same | 9915697.50 | 10113311.76 | 0.98 | opensuse-leap 15.3 | X64 | Intel Core i7-7700 CPU 3.60GHz (Kaby Lake) |
| Same | 13491174.81 | 13389165.63 | 1.01 | ubuntu 18.04 | X64 | Intel Xeon CPU E5-1650 v4 3.60GHz |
| Same | 17370649.54 | 16005520.13 | 1.09 | ubuntu 18.04 | X64 | Intel Core i7-2720QM CPU 2.20GHz (Sandy Bridge) |
| Slower | 180336900.00 | 209815000.00 | 0.86 | Windows 10 | Arm | Microsoft SQ1 3.0 GHz |
| Same | 194855158.00 | 199422552.00 | 0.98 | ubuntu 18.04 | Arm | ARMv7 Processor rev 3 (v7l) |
| Same | 95764800.00 | 103428275.00 | 0.93 | Windows 10 | X86 | Intel Xeon CPU E5-1650 v4 3.60GHz |
| Same | 92642500.00 | 100944225.00 | 0.92 | Windows 11 | X86 | AMD Ryzen Threadripper PRO 3945WX 12-Cores |
| Faster | 332525100.00 | 184955950.00 | 1.80 | Windows 11 | X86 | Intel Core i7-10510U CPU 1.80GHz |
| Faster | 277613675.00 | 187145750.00 | 1.48 | Windows 7 SP1 | X86 | Intel Core i7-7700 CPU 3.60GHz (Kaby Lake) |
| Same | 18966713.69 | 18777427.62 | 1.01 | macOS Monterey 12.2.1 | X64 | Intel Core i7-5557U CPU 3.10GHz (Broadwell) |
| Same | 16605661.57 | 17217161.62 | 0.96 | macOS Monterey 12.3.1 | X64 | Intel Core i7-4870HQ CPU 2.50GHz (Haswell) |