Blazor Wasm limited to 1 GB of memory

[verdie-g]

Description

OutOfMemoryExceptions are thrown after allocating more than ~1 GB in a Blazor Wasm app.

This is a duplicate of https://github.com/dotnet/aspnetcore/issues/55694 that got closed but the issue is not solved.

Reproduction Steps

1. dotnet new blazorwasm -n BlazorTest
2. Add this method to Home.razor

   protected override void OnInitialized()
   {
   const int bufferSize = 64 * 1000;
   const int oneGig = 1_000_000_000;
   List<byte[]> list = [];
   for (int i = 0; i < oneGig / bufferSize; i += 1)
   {
       list.Add(new byte[bufferSize]);
   }
   }

3. dotnet run --project BlazorTest
4. Observe OOM in the console

Expected behavior

Because wasm uses a 32-bits addressing, I would expect to be able to use 4 GB of memory.

Actual behavior

OOM is thrown after allocating ~1 GB of memory.

System.OutOfMemoryException: Out of memory
   at BlazorTest.Pages.Home.OnInitialized() in /home/gverdier/repos/BlazorTest/Pages/Home.razor:line 17
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()

Regression?

No response

Known Workarounds

No response

Configuration

.NET: 8.0.100 OS: Ubuntu x64 Browser: Google Chrome 125

Other information

No response

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[lewing]

Did you try setting EmccMaximumHeapSize to something larger?

[verdie-g]

I've just tried setting

<EmccMaximumHeapSize>4294967296</EmccMaximumHeapSize>

in my csproj but it still OOMs.

[lewing]

can you try setting EmccInitialHeapSize to something large as well?

[verdie-g]

Same behavior with

<EmccInitialHeapSize>3000000000</EmccInitialHeapSize>
<EmccMaximumHeapSize>4294967296</EmccMaximumHeapSize>