Benchmark numbers for Dev Drive initial release in Win11 22H2 10.0.22621.2506 (late October 2023 with optional Oct 25 OS update).
16-core Azure AMD v5 VM.
ExtentsOnly = Files to be copied/cloned were created only by setting the file extents. WroteData = Files were also written to. ReFS/Dev Drive behaves differently in this case.
BenchmarkDotNet=v0.13.2, OS=Windows 11 (10.0.22621.2506), VM=Hyper-V AMD EPYC 7763, 1 CPU, 16 logical and 8 physical cores .NET SDK=6.0.416 [Host] : .NET 6.0.24 (6.0.2423.51814), X64 RyuJIT AVX2 Job-GPSHJH : .NET 6.0.24 (6.0.2423.51814), X64 RyuJIT AVX2
| Method | FileSize | FileContents | Mean | Error | StdDev | Median | Ratio | RatioSD |
|---|---|---|---|---|---|---|---|---|
| File.Copy | 0 | ExtentsOnly | 179.1 us | 3.58 us | 3.83 us | 177.6 us | 1.00 | 0.00 |
| CoW | 0 | ExtentsOnly | 169.3 us | 3.38 us | 7.34 us | 167.0 us | 0.99 | 0.05 |
| File.Copy | 0 | WroteData | 178.4 us | 3.54 us | 5.62 us | 175.8 us | 1.00 | 0.00 |
| CoW | 0 | WroteData | 168.9 us | 3.01 us | 6.08 us | 167.3 us | 0.95 | 0.03 |
| File.Copy | 1 | ExtentsOnly | 393.9 us | 6.77 us | 7.52 us | 394.9 us | 1.00 | 0.00 |
| CoW | 1 | ExtentsOnly | 201.4 us | 3.34 us | 2.61 us | 201.1 us | 0.51 | 0.01 |
| File.Copy | 1 | WroteData | 384.1 us | 7.68 us | 11.49 us | 384.3 us | 1.00 | 0.00 |
| CoW | 1 | WroteData | 375.7 us | 4.98 us | 4.16 us | 376.3 us | 0.98 | 0.03 |
| File.Copy | 1024 | ExtentsOnly | 406.6 us | 7.32 us | 10.96 us | 407.7 us | 1.00 | 0.00 |
| CoW | 1024 | ExtentsOnly | 233.9 us | 4.59 us | 6.43 us | 232.4 us | 0.58 | 0.03 |
| File.Copy | 1024 | WroteData | 408.3 us | 8.14 us | 8.00 us | 410.2 us | 1.00 | 0.00 |
| CoW | 1024 | WroteData | 434.6 us | 8.85 us | 25.10 us | 425.6 us | 1.07 | 0.05 |
| File.Copy | 16384 | ExtentsOnly | 384.8 us | 6.60 us | 13.18 us | 385.7 us | 1.00 | 0.00 |
| CoW | 16384 | ExtentsOnly | 231.9 us | 4.62 us | 6.48 us | 230.0 us | 0.60 | 0.03 |
| File.Copy | 16384 | WroteData | 387.0 us | 7.29 us | 20.07 us | 381.1 us | 1.00 | 0.00 |
| CoW | 16384 | WroteData | 233.9 us | 4.68 us | 6.56 us | 232.6 us | 0.61 | 0.04 |
| File.Copy | 262144 | ExtentsOnly | 437.0 us | 8.32 us | 6.94 us | 435.9 us | 1.00 | 0.00 |
| CoW | 262144 | ExtentsOnly | 231.4 us | 4.54 us | 5.41 us | 230.7 us | 0.53 | 0.01 |
| File.Copy | 262144 | WroteData | 419.8 us | 7.47 us | 6.23 us | 419.1 us | 1.00 | 0.00 |
| CoW | 262144 | WroteData | 232.7 us | 3.19 us | 6.22 us | 232.1 us | 0.55 | 0.01 |
| File.Copy | 1048576 | ExtentsOnly | 630.0 us | 11.96 us | 28.19 us | 617.1 us | 1.00 | 0.00 |
| CoW | 1048576 | ExtentsOnly | 231.7 us | 4.57 us | 5.94 us | 230.1 us | 0.36 | 0.02 |
| File.Copy | 1048576 | WroteData | 630.2 us | 12.55 us | 31.49 us | 614.8 us | 1.00 | 0.00 |
| CoW | 1048576 | WroteData | 232.4 us | 4.26 us | 3.56 us | 233.2 us | 0.37 | 0.02 |
| File.Copy | 16777216 | ExtentsOnly | 3,419.0 us | 29.44 us | 24.59 us | 3,417.9 us | 1.00 | 0.00 |
| CoW | 16777216 | ExtentsOnly | 253.0 us | 5.03 us | 9.20 us | 250.2 us | 0.08 | 0.00 |
| File.Copy | 16777216 | WroteData | 3,486.9 us | 30.07 us | 28.13 us | 3,486.5 us | 1.00 | 0.00 |
| CoW | 16777216 | WroteData | 253.5 us | 3.96 us | 5.92 us | 252.2 us | 0.07 | 0.00 |
| Method | FileSize | FileContents | Mean | Error | StdDev | Median | Ratio | RatioSD |
|---|---|---|---|---|---|---|---|---|
| File.Copy | 0 | ExtentsOnly | 183.7 us | 3.59 us | 3.69 us | 182.8 us | 1.00 | 0.00 |
| CoW | 0 | ExtentsOnly | 167.8 us | 3.33 us | 5.84 us | 165.9 us | 0.93 | 0.04 |
| File.Copy | 0 | WroteData | 176.6 us | 2.82 us | 3.13 us | 176.1 us | 1.00 | 0.00 |
| CoW | 0 | WroteData | 169.7 us | 3.37 us | 7.04 us | 166.4 us | 1.00 | 0.04 |
| File.Copy | 1 | ExtentsOnly | 402.1 us | 11.48 us | 33.86 us | 389.2 us | 1.00 | 0.00 |
| CoW | 1 | ExtentsOnly | 204.1 us | 4.02 us | 6.26 us | 202.5 us | 0.51 | 0.04 |
| File.Copy | 1 | WroteData | 397.7 us | 10.40 us | 30.50 us | 386.6 us | 1.00 | 0.00 |
| CoW | 1 | WroteData | 384.4 us | 7.59 us | 8.44 us | 382.2 us | 0.96 | 0.07 |
| File.Copy | 1024 | ExtentsOnly | 407.5 us | 8.09 us | 10.81 us | 409.4 us | 1.00 | 0.00 |
| CoW | 1024 | ExtentsOnly | 232.4 us | 3.12 us | 4.77 us | 231.1 us | 0.57 | 0.02 |
| File.Copy | 1024 | WroteData | 409.7 us | 7.26 us | 13.46 us | 409.4 us | 1.00 | 0.00 |
| CoW | 1024 | WroteData | 423.8 us | 8.28 us | 11.34 us | 420.6 us | 1.03 | 0.05 |
| File.Copy | 16384 | ExtentsOnly | 386.3 us | 6.51 us | 14.55 us | 385.1 us | 1.00 | 0.00 |
| CoW | 16384 | ExtentsOnly | 234.6 us | 4.55 us | 7.36 us | 232.8 us | 0.61 | 0.03 |
| File.Copy | 16384 | WroteData | 382.8 us | 7.41 us | 16.73 us | 381.2 us | 1.00 | 0.00 |
| CoW | 16384 | WroteData | 233.3 us | 4.55 us | 6.81 us | 232.8 us | 0.60 | 0.03 |
| File.Copy | 262144 | ExtentsOnly | 438.3 us | 9.49 us | 27.69 us | 424.3 us | 1.00 | 0.00 |
| CoW | 262144 | ExtentsOnly | 233.1 us | 4.12 us | 6.41 us | 231.8 us | 0.53 | 0.03 |
| File.Copy | 262144 | WroteData | 439.2 us | 10.13 us | 29.70 us | 424.8 us | 1.00 | 0.00 |
| CoW | 262144 | WroteData | 232.6 us | 3.65 us | 5.24 us | 231.6 us | 0.54 | 0.03 |
| File.Copy | 1048576 | ExtentsOnly | 634.6 us | 12.69 us | 30.40 us | 626.0 us | 1.00 | 0.00 |
| CoW | 1048576 | ExtentsOnly | 234.7 us | 4.04 us | 6.86 us | 233.2 us | 0.37 | 0.02 |
| File.Copy | 1048576 | WroteData | 630.5 us | 12.60 us | 32.97 us | 616.9 us | 1.00 | 0.00 |
| CoW | 1048576 | WroteData | 233.9 us | 4.62 us | 8.34 us | 232.7 us | 0.37 | 0.02 |
| File.Copy | 16777216 | ExtentsOnly | 3,496.3 us | 69.08 us | 134.74 us | 3,440.1 us | 1.00 | 0.00 |
| CoW | 16777216 | ExtentsOnly | 250.9 us | 4.04 us | 5.39 us | 249.9 us | 0.07 | 0.00 |
| File.Copy | 16777216 | WroteData | 3,575.5 us | 37.86 us | 35.41 us | 3,570.5 us | 1.00 | 0.00 |
| CoW | 16777216 | WroteData | 252.4 us | 3.61 us | 6.69 us | 251.9 us | 0.07 | 0.00 |