fix(threads): missing max threads parameter

doc/features-environment-variables.md

@@ -27,5 +27,6 @@ The bootstrapper provides a set of environment variables that reflect the config
 - `UNO_BOOTSTRAP_APP_BASE`, which specifies the location of the app content from the base. Useful to reach assets deployed using the `UnoDeploy="Package"` mode.
 - `UNO_BOOTSTRAP_WEBAPP_BASE_PATH`, which specifies the base location of the webapp. This parameter is used in the context of deep-linking (through the `WasmShellWebAppBasePath` property). This property must contain a trailing `/` and its default is `./`.
 - `UNO_BOOTSTRAP_EMSCRIPTEN_MAXIMUM_MEMORY`, which optionally specifies the maximum memory available to the WebAssembly module. 
+- `UNO_BOOTSTRAP_MAX_THREADS`, which provides the maximum number of threads that can be created.
 
 Those variables can be accessed through [Environment.GetEnvironmentVariable](https://docs.microsoft.com/en-us/dotnet/api/system.environment.getenvironmentvariable).

doc/features-threading.md

@@ -17,7 +17,7 @@ Threading support can be detected at runtime by using the [`UNO_BOOTSTRAP_MONO_R
 
 ### Controlling the browser thread pool size
 
-By default, the runtime pre-creates a set of 4 Web Workers available to WebAssembly threads, and the .NET Runtime will reuse the workers as threads stop. 
+By default, the runtime pre-creates a set of 4 WebWorkers available to WebAssembly threads, and the .NET Runtime will reuse the workers as threads stop. This value is used by the `ThreadPool` and `Tasks` subsystems.
 
 To change the number of threads available to the app, use the following:
 ```xml
@@ -26,6 +26,8 @@ To change the number of threads available to the app, use the following:
 </PropertyGroup>
 ```
 
+The maximum number of threads can be determined by the `UNO_BOOTSTRAP_MAX_THREADS` environment variable.
+
 ### Restrictions
 WebAssembly Threads are using the `SharedArrayBuffer` browser feature, which is disabled in most cases for security reasons. 
 

src/Uno.Wasm.Bootstrap/ShellTask.cs

@@ -772,7 +772,7 @@ private void RunPackager()
  var pthreadPoolSizeParam = $"--pthread-pool-size={PThreadsPoolSize}";
 
  var enableICUParam = EnableNetCoreICU ? "--icu" : "";
- var monovmparams = $"--framework=net5 --runtimepack-dir=\"{AlignPath(MonoWasmSDKPath)}\" {enableICUParam} ";
+ var monovmparams = $"--framework=net5 --runtimepack-dir=\"{AlignPath(MonoWasmSDKPath)}\" {enableICUParam} {pthreadPoolSizeParam}";
  var pass1ResponseContent = $"{runtimeConfigurationParam} {appDirParm} {monovmparams} --zlib {debugOption} {referencePathsParameter} \"{AlignPath(TryConvertLongPath(Path.GetFullPath(Assembly)))}\"";
 
  var packagerPass1ResponseFile = Path.Combine(workAotPath, "packager-pass1.rsp");
@@ -1866,6 +1866,11 @@ private void GenerateConfig()
  AddEnvironmentVariable("UNO_BOOTSTRAP_APP_BASE", _remoteBasePackagePath);
  AddEnvironmentVariable("UNO_BOOTSTRAP_WEBAPP_BASE_PATH", WebAppBasePath);
 
+ if (EnableThreads)
+ {
+ AddEnvironmentVariable("UNO_BOOTSTRAP_MAX_THREADS", PThreadsPoolSize.ToString());
+ }
+
  if (ExtraEmccFlags?.Any(f => f.ItemSpec?.Contains("MAXIMUM_MEMORY=4GB") ?? false) ?? false)
  {
  // Detects the use of the 4GB flag: https://v8.dev/blog/4gb-wasm-memory