[Perf] Regressions in System.IO.Tests.Perf_FileStream

### Run Information

Architecture | x64
-- | --
OS | Windows 10.0.18362
Baseline | [a06eccb3600b702d911bcdf8fb0caa50970858d9](https://github.com/dotnet/runtime/commit/a06eccb3600b702d911bcdf8fb0caa50970858d9)
Compare | [98038888bfb4215a44002b2046eae9ff166087f5](https://github.com/dotnet/runtime/commit/98038888bfb4215a44002b2046eae9ff166087f5)
Diff | [Diff](https://github.com/dotnet/runtime/compare/a06eccb3600b702d911bcdf8fb0caa50970858d9...98038888bfb4215a44002b2046eae9ff166087f5)


### Regressions in System.IO.Tests.Perf_FileStream

Benchmark | Baseline | Test | Test/Base | Baseline IR | Compare IR | IR Ratio | Baseline ETL | Compare ETL
-- | -- | -- | -- | -- | -- | -- | -- | --
[FlushAsync](<https://pvscmdupload.blob.core.windows.net/reports/allTestHistory/refs/heads/main_x64_Windows 10.0.18362/System.IO.Tests.Perf_FileStream.FlushAsync(fileSize%3a%201024%2c%20options%3a%20None).html>) | 2.62 ms | 3.67 ms | 1.40 | | | | [Trace](https://helixri107v0xdeko0k025g8.blob.core.windows.net/results-9b28c6d7e751485b92/Collect%20System.IO.Tests.Perf_FileStream.FlushAsync/artifacts/BenchmarkDotNet.Artifacts/System.IO.Tests.Perf_FileStream.FlushAsync%28fileSize_%201024%2C%20options_%20None%29-20210413-020924.etl?sv=2019-07-07&se=2021-07-12T09%3A07%3A09Z&sr=c&sp=rl&sig=X%2FwBo%2FcFiidVFYKJkSzpqtvi30JEW6bXnxZtjcBB6Ok%3D) | [Trace](https://helixri107v0xdeko0k025g8.blob.core.windows.net/results-32e73520bace483383/Collect%20System.IO.Tests.Perf_FileStream.FlushAsync/artifacts/BenchmarkDotNet.Artifacts/System.IO.Tests.Perf_FileStream.FlushAsync%28fileSize_%201024%2C%20options_%20None%29-20210413-021004.etl?sv=2019-07-07&se=2021-07-12T09%3A07%3A09Z&sr=c&sp=rl&sig=t%2F9HaiLhtYvou9STgjPvuoT%2BnzTwMA6y3R%2FgjN2%2FXq8%3D)
[ReadAsync](<https://pvscmdupload.blob.core.windows.net/reports/allTestHistory/refs/heads/main_x64_Windows 10.0.18362/System.IO.Tests.Perf_FileStream.ReadAsync(fileSize%3a%201024%2c%20userBufferSize%3a%201024%2c%20options%3a%20Asynchronous).html>) | 43.11 μs | 55.59 μs | 1.29 | | | | [Trace](https://helixri107v0xdeko0k025g8.blob.core.windows.net/results-b22d0f629648473a80/Collect%20System.IO.Tests.Perf_FileStream.ReadAsync/artifacts/BenchmarkDotNet.Artifacts/System.IO.Tests.Perf_FileStream.ReadAsync%28fileSize_%201024%2C%20userBufferSize_%201024%2C%20options_%20Asynchronous%29-20210413-021104.etl?sv=2019-07-07&se=2021-07-12T09%3A07%3A29Z&sr=c&sp=rl&sig=gwufHG1%2BzuG8DG330Icq2cieI7NMXQx4fPobDXEmyX8%3D) | [Trace](https://helixri107v0xdeko0k025g8.blob.core.windows.net/results-804c0d9a5bde4a1c91/Collect%20System.IO.Tests.Perf_FileStream.ReadAsync/artifacts/BenchmarkDotNet.Artifacts/System.IO.Tests.Perf_FileStream.ReadAsync%28fileSize_%201024%2C%20userBufferSize_%201024%2C%20options_%20Asynchronous%29-20210413-020944.etl?sv=2019-07-07&se=2021-07-12T09%3A07%3A30Z&sr=c&sp=rl&sig=A5sy2PYWAYmThnTKVuCotnF0QlC3c%2F%2B1bEjIywBZTjY%3D)

![graph](<https://pvscmdupload.blob.core.windows.net/autofilereport/autofilereports/04_13_2021/refs/heads/main_x64_Windows%2010.0.18362_Regression/System.IO.Tests.Perf_FileStream_1.png>)
![graph](<https://pvscmdupload.blob.core.windows.net/autofilereport/autofilereports/04_13_2021/refs/heads/main_x64_Windows%2010.0.18362_Regression/System.IO.Tests.Perf_FileStream_9.png>)
[Historical Data in Reporting System](<https://pvscmdupload.blob.core.windows.net/autofilereport/autofilereports/04_13_2021/refs/heads/main_x64_Windows%2010.0.18362_Regression/System.IO.Tests.Perf_FileStream.html>)

### Repro

```cmd
git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f netcoreapp5.0 --filter 'System.IO.Tests.Perf_FileStream*'
```
<details>

### Payloads

[Baseline](<https://helixdi107v0xdeko0k025g8.blob.core.windows.net/helix-job-3e73e24e-30c0-4ade-b0b3-f555c2aa8ea3c0b7154491c477397/945863f2-50a2-40b7-bc75-546918f79618.zip?sv=2019-07-07&se=2021-05-08T05%3A55%3A56Z&sr=c&sp=rl&sig=G6EEdXJIr6YS%2BU5LPeOccdGG8bdYQLdiimXQy7feSP8%3D>)
[Compare](<https://helixdi107v0xdeko0k025g8.blob.core.windows.net/helix-job-667913af-c0ed-4949-8cab-c2f81adc0dfa1ca5d9fdfef424e99/a45332c1-313e-49b2-8353-f54382295c80.zip?sv=2019-07-07&se=2021-05-09T02%3A10%3A09Z&sr=c&sp=rl&sig=hbOXH7rvOR7BZh3Iy3UJSWBy5LWK6lTVJq1bWtgR%2FmM%3D>)

### Histogram
#### System.IO.Tests.Perf_FileStream.FlushAsync(fileSize: 1024, options: None)

```log

```
### Baseline Jit Disasm

```assembly
; System.IO.Tests.Perf_FileStream.FlushAsync(Int64, System.IO.FileOptions)
       sub       rsp,58
       vxorps    xmm4,xmm4,xmm4
       vmovdqa   xmmword ptr [rsp+20],xmm4
       vmovdqa   xmmword ptr [rsp+30],xmm4
       vmovdqa   xmmword ptr [rsp+40],xmm4
       xor       eax,eax
       mov       [rsp+50],rax
       xor       eax,eax
       mov       [rsp+48],rax
       mov       [rsp+20],rcx
       mov       [rsp+30],rdx
       mov       [rsp+3C],r8d
       mov       dword ptr [rsp+38],0FFFFFFFF
       lea       rcx,[rsp+20]
       call      System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<FlushAsync>d__36, MicroBenchmarks]](<FlushAsync>d__36 ByRef)
       mov       rax,[rsp+48]
       test      rax,rax
       je        short M00_L01
M00_L00:
       add       rsp,58
       ret
M00_L01:
       lea       rcx,[rsp+48]
       call      System.Runtime.CompilerServices.AsyncTaskMethodBuilder.InitializeTaskAsPromise()
       jmp       short M00_L00
; Total bytes of code 100
```
```assembly
; System.Threading.Tasks.Task.GetAwaiter()
       mov       rax,rcx
       ret
; Total bytes of code 4
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter.GetResult()
       mov       rcx,[rcx]
       mov       eax,[rcx+34]
       and       eax,11000000
       cmp       eax,1000000
       je        short M02_L00
       jmp       near ptr System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
M02_L00:
       ret
; Total bytes of code 24
```
```assembly
; System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<FlushAsync>d__36, MicroBenchmarks]](<FlushAsync>d__36 ByRef)
       push      rbp
       push      rsi
       sub       rsp,48
       lea       rbp,[rsp+50]
       mov       [rbp+0FFD0],rsp
       mov       rsi,rcx
       cmp       [rsi],esi
       mov       rcx,7FF999D34540
       mov       edx,281
       call      CORINFO_HELP_GETSHARED_GCTHREADSTATIC_BASE
       mov       rax,[rax+20]
       test      rax,rax
       jne       short M03_L00
       call      System.Threading.Thread.InitializeCurrentThread()
M03_L00:
       mov       [rbp+0FFF0],rax
       mov       rdx,[rax+8]
       mov       [rbp+0FFE8],rdx
       mov       rax,[rax+10]
       mov       [rbp+0FFE0],rax
       mov       rcx,rsi
       call      System.IO.Tests.Perf_FileStream+<FlushAsync>d__36.MoveNext()
       nop
       mov       rax,[rbp+0FFE0]
       mov       rcx,[rbp+0FFF0]
       cmp       rax,[rcx+10]
       je        short M03_L01
       lea       rcx,[rcx+10]
       mov       rdx,rax
       call      CORINFO_HELP_ASSIGN_REF
       mov       rcx,[rbp+0FFF0]
M03_L01:
       mov       r8,[rcx+8]
       mov       rdx,[rbp+0FFE8]
       cmp       rdx,r8
       je        short M03_L02
       call      System.Threading.ExecutionContext.RestoreChangedContextToThread(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ExecutionContext)
M03_L02:
       nop
       lea       rsp,[rbp+0FFF8]
       pop       rsi
       pop       rbp
       ret
       push      rbp
       push      rsi
       sub       rsp,28
       mov       rbp,[rcx+20]
       mov       [rsp+20],rbp
       lea       rbp,[rbp+50]
       mov       rdx,[rbp+0FFE0]
       mov       rcx,[rbp+0FFF0]
       cmp       rdx,[rcx+10]
       je        short M03_L03
       lea       rcx,[rcx+10]
       call      CORINFO_HELP_ASSIGN_REF
       mov       rcx,[rbp+0FFF0]
M03_L03:
       mov       r8,[rcx+8]
       mov       rdx,[rbp+0FFE8]
       cmp       rdx,r8
       je        short M03_L04
       call      System.Threading.ExecutionContext.RestoreChangedContextToThread(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ExecutionContext)
M03_L04:
       nop
       add       rsp,28
       pop       rsi
       pop       rbp
       ret
; Total bytes of code 211
```


### Compare Jit Disasm

```assembly
; System.IO.Tests.Perf_FileStream.FlushAsync(Int64, System.IO.FileOptions)
       sub       rsp,58
       vxorps    xmm4,xmm4,xmm4
       vmovdqa   xmmword ptr [rsp+20],xmm4
       vmovdqa   xmmword ptr [rsp+30],xmm4
       vmovdqa   xmmword ptr [rsp+40],xmm4
       xor       eax,eax
       mov       [rsp+50],rax
       xor       eax,eax
       mov       [rsp+48],rax
       mov       [rsp+20],rcx
       mov       [rsp+30],rdx
       mov       [rsp+3C],r8d
       mov       dword ptr [rsp+38],0FFFFFFFF
       lea       rcx,[rsp+20]
       call      System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<FlushAsync>d__36, MicroBenchmarks]](<FlushAsync>d__36 ByRef)
       mov       rax,[rsp+48]
       test      rax,rax
       je        short M00_L01
M00_L00:
       add       rsp,58
       ret
M00_L01:
       lea       rcx,[rsp+48]
       call      System.Runtime.CompilerServices.AsyncTaskMethodBuilder.InitializeTaskAsPromise()
       jmp       short M00_L00
; Total bytes of code 100
```
```assembly
; System.Threading.Tasks.Task.GetAwaiter()
       mov       rax,rcx
       ret
; Total bytes of code 4
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter.GetResult()
       mov       rcx,[rcx]
       mov       eax,[rcx+34]
       and       eax,11000000
       cmp       eax,1000000
       je        short M02_L00
       jmp       near ptr System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
M02_L00:
       ret
; Total bytes of code 24
```
```assembly
; System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<FlushAsync>d__36, MicroBenchmarks]](<FlushAsync>d__36 ByRef)
       push      rbp
       push      rsi
       sub       rsp,48
       lea       rbp,[rsp+50]
       mov       [rbp+0FFD0],rsp
       mov       rsi,rcx
       cmp       [rsi],esi
       mov       rcx,7FFF11044550
       mov       edx,281
       call      CORINFO_HELP_GETSHARED_GCTHREADSTATIC_BASE
       mov       rax,[rax+20]
       test      rax,rax
       jne       short M03_L00
       call      System.Threading.Thread.InitializeCurrentThread()
M03_L00:
       mov       [rbp+0FFF0],rax
       mov       rdx,[rax+8]
       mov       [rbp+0FFE8],rdx
       mov       rax,[rax+10]
       mov       [rbp+0FFE0],rax
       mov       rcx,rsi
       call      System.IO.Tests.Perf_FileStream+<FlushAsync>d__36.MoveNext()
       nop
       mov       rax,[rbp+0FFE0]
       mov       rcx,[rbp+0FFF0]
       cmp       rax,[rcx+10]
       je        short M03_L01
       lea       rcx,[rcx+10]
       mov       rdx,rax
       call      CORINFO_HELP_ASSIGN_REF
       mov       rcx,[rbp+0FFF0]
M03_L01:
       mov       r8,[rcx+8]
       mov       rdx,[rbp+0FFE8]
       cmp       rdx,r8
       je        short M03_L02
       call      System.Threading.ExecutionContext.RestoreChangedContextToThread(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ExecutionContext)
M03_L02:
       nop
       lea       rsp,[rbp+0FFF8]
       pop       rsi
       pop       rbp
       ret
       push      rbp
       push      rsi
       sub       rsp,28
       mov       rbp,[rcx+20]
       mov       [rsp+20],rbp
       lea       rbp,[rbp+50]
       mov       rdx,[rbp+0FFE0]
       mov       rcx,[rbp+0FFF0]
       cmp       rdx,[rcx+10]
       je        short M03_L03
       lea       rcx,[rcx+10]
       call      CORINFO_HELP_ASSIGN_REF
       mov       rcx,[rbp+0FFF0]
M03_L03:
       mov       r8,[rcx+8]
       mov       rdx,[rbp+0FFE8]
       cmp       rdx,r8
       je        short M03_L04
       call      System.Threading.ExecutionContext.RestoreChangedContextToThread(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ExecutionContext)
M03_L04:
       nop
       add       rsp,28
       pop       rsi
       pop       rbp
       ret
; Total bytes of code 211
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
       push      rsi
       sub       rsp,20
       mov       rsi,rcx
       mov       ecx,[rsi+34]
       test      ecx,1600000
       jne       short M04_L00
       mov       rcx,rsi
       xor       r8d,r8d
       mov       edx,0FFFFFFFF
       call      System.Threading.Tasks.Task.InternalWaitCore(Int32, System.Threading.CancellationToken)
M04_L00:
       mov       rcx,rsi
       call      System.Threading.Tasks.Task.NotifyDebuggerOfWaitCompletionIfNecessary()
       mov       ecx,[rsi+34]
       and       ecx,1600000
       cmp       ecx,1000000
       je        short M04_L01
       mov       rcx,rsi
       call      System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(System.Threading.Tasks.Task)
M04_L01:
       nop
       add       rsp,20
       pop       rsi
       ret
; Total bytes of code 75
```


#### System.IO.Tests.Perf_FileStream.ReadAsync(fileSize: 1024, userBufferSize: 1024, options: Asynchronous)

```log

```
### Baseline Jit Disasm

```assembly
; System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions)
       sub       rsp,28
       mov       dword ptr [rsp+20],1000
       call      System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions, Int32)
       nop
       add       rsp,28
       ret
; Total bytes of code 23
```
```assembly
; System.Threading.Tasks.Task`1[[System.Int64, System.Private.CoreLib]].GetAwaiter()
       mov       rax,rcx
       ret
; Total bytes of code 4
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter`1[[System.Int64, System.Private.CoreLib]].GetResult()
       push      rsi
       sub       rsp,20
       mov       rsi,rcx
       mov       rcx,[rsi]
       mov       eax,[rcx+34]
       and       eax,11000000
       cmp       eax,1000000
       je        short M02_L00
       call      System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
M02_L00:
       mov       rax,[rsi]
       mov       rax,[rax+38]
       add       rsp,20
       pop       rsi
       ret
; Total bytes of code 44
```
```assembly
; System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions, Int32)
       sub       rsp,88
       xor       eax,eax
       mov       [rsp+28],rax
       vxorps    xmm4,xmm4,xmm4
       vmovdqa   xmmword ptr [rsp+30],xmm4
       vmovdqa   xmmword ptr [rsp+40],xmm4
       vmovdqa   xmmword ptr [rsp+50],xmm4
       vmovdqa   xmmword ptr [rsp+60],xmm4
       vmovdqa   xmmword ptr [rsp+70],xmm4
       mov       [rsp+80],rax
       xor       eax,eax
       mov       [rsp+58],rax
       mov       [rsp+28],rcx
       mov       [rsp+38],rdx
       mov       [rsp+4C],r8d
       mov       [rsp+54],r9d
       mov       ecx,[rsp+0B0]
       mov       [rsp+50],ecx
       mov       dword ptr [rsp+48],0FFFFFFFF
       lea       rcx,[rsp+28]
       call      System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<ReadAsync>d__31, MicroBenchmarks]](<ReadAsync>d__31 ByRef)
       mov       rax,[rsp+58]
       test      rax,rax
       jne       short M03_L00
       lea       rcx,[rsp+58]
       call      System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.Int64, System.Private.CoreLib]].InitializeTaskAsPromise()
M03_L00:
       nop
       add       rsp,88
       ret
; Total bytes of code 141
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
       push      rsi
       sub       rsp,20
       mov       rsi,rcx
       mov       ecx,[rsi+34]
       test      ecx,1600000
       jne       short M04_L00
       mov       rcx,rsi
       xor       r8d,r8d
       mov       edx,0FFFFFFFF
       call      System.Threading.Tasks.Task.InternalWaitCore(Int32, System.Threading.CancellationToken)
M04_L00:
       mov       rcx,rsi
       call      System.Threading.Tasks.Task.NotifyDebuggerOfWaitCompletionIfNecessary()
       mov       ecx,[rsi+34]
       and       ecx,1600000
       cmp       ecx,1000000
       je        short M04_L01
       mov       rcx,rsi
       call      System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(System.Threading.Tasks.Task)
M04_L01:
       nop
       add       rsp,20
       pop       rsi
       ret
; Total bytes of code 75
```


### Compare Jit Disasm

```assembly
; System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions)
       sub       rsp,28
       mov       dword ptr [rsp+20],1000
       call      System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions, Int32)
       nop
       add       rsp,28
       ret
; Total bytes of code 23
```
```assembly
; System.Threading.Tasks.Task`1[[System.Int64, System.Private.CoreLib]].GetAwaiter()
       mov       rax,rcx
       ret
; Total bytes of code 4
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter`1[[System.Int64, System.Private.CoreLib]].GetResult()
       push      rsi
       sub       rsp,20
       mov       rsi,rcx
       mov       rcx,[rsi]
       mov       eax,[rcx+34]
       and       eax,11000000
       cmp       eax,1000000
       je        short M02_L00
       call      System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
M02_L00:
       mov       rax,[rsi]
       mov       rax,[rax+38]
       add       rsp,20
       pop       rsi
       ret
; Total bytes of code 44
```
```assembly
; System.IO.Tests.Perf_FileStream.ReadAsync(Int64, Int32, System.IO.FileOptions, Int32)
       sub       rsp,88
       xor       eax,eax
       mov       [rsp+28],rax
       vxorps    xmm4,xmm4,xmm4
       vmovdqa   xmmword ptr [rsp+30],xmm4
       vmovdqa   xmmword ptr [rsp+40],xmm4
       vmovdqa   xmmword ptr [rsp+50],xmm4
       vmovdqa   xmmword ptr [rsp+60],xmm4
       vmovdqa   xmmword ptr [rsp+70],xmm4
       mov       [rsp+80],rax
       xor       eax,eax
       mov       [rsp+58],rax
       mov       [rsp+28],rcx
       mov       [rsp+38],rdx
       mov       [rsp+4C],r8d
       mov       [rsp+54],r9d
       mov       ecx,[rsp+0B0]
       mov       [rsp+50],ecx
       mov       dword ptr [rsp+48],0FFFFFFFF
       lea       rcx,[rsp+28]
       call      System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[System.IO.Tests.Perf_FileStream+<ReadAsync>d__31, MicroBenchmarks]](<ReadAsync>d__31 ByRef)
       mov       rax,[rsp+58]
       test      rax,rax
       jne       short M03_L00
       lea       rcx,[rsp+58]
       call      System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.Int64, System.Private.CoreLib]].InitializeTaskAsPromise()
M03_L00:
       nop
       add       rsp,88
       ret
; Total bytes of code 141
```
```assembly
; System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
       push      rsi
       sub       rsp,20
       mov       rsi,rcx
       mov       ecx,[rsi+34]
       test      ecx,1600000
       jne       short M04_L00
       mov       rcx,rsi
       xor       r8d,r8d
       mov       edx,0FFFFFFFF
       call      System.Threading.Tasks.Task.InternalWaitCore(Int32, System.Threading.CancellationToken)
M04_L00:
       mov       rcx,rsi
       call      System.Threading.Tasks.Task.NotifyDebuggerOfWaitCompletionIfNecessary()
       mov       ecx,[rsi+34]
       and       ecx,1600000
       cmp       ecx,1000000
       je        short M04_L01
       mov       rcx,rsi
       call      System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(System.Threading.Tasks.Task)
M04_L01:
       nop
       add       rsp,20
       pop       rsi
       ret
; Total bytes of code 75
```




### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

</details>


Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

[Perf] Regressions in System.IO.Tests.Perf_FileStream #51256

Run Information

Regressions in System.IO.Tests.Perf_FileStream

Repro

Payloads

Histogram

System.IO.Tests.Perf_FileStream.FlushAsync(fileSize: 1024, options: None)

Baseline Jit Disasm

Compare Jit Disasm

System.IO.Tests.Perf_FileStream.ReadAsync(fileSize: 1024, userBufferSize: 1024, options: Asynchronous)

Baseline Jit Disasm

Compare Jit Disasm

Docs

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Architecture	x64
OS	Windows 10.0.18362
Baseline	a06eccb3600b702d911bcdf8fb0caa50970858d9
Compare	98038888bfb4215a44002b2046eae9ff166087f5
Diff	Diff

Benchmark	Baseline	Test	Test/Base	Baseline IR	Compare IR	IR Ratio	Baseline ETL	Compare ETL
FlushAsync	2.62 ms	3.67 ms	1.40				Trace	Trace
ReadAsync	43.11 μs	55.59 μs	1.29				Trace	Trace

[Perf] Regressions in System.IO.Tests.Perf_FileStream #51256

Description

Run Information

Regressions in System.IO.Tests.Perf_FileStream

Repro

Payloads

Histogram

System.IO.Tests.Perf_FileStream.FlushAsync(fileSize: 1024, options: None)

Baseline Jit Disasm

Compare Jit Disasm

System.IO.Tests.Perf_FileStream.ReadAsync(fileSize: 1024, userBufferSize: 1024, options: Asynchronous)

Baseline Jit Disasm

Compare Jit Disasm

Docs

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions