Skip to content

Reduce allocations within ReactiveObject and ReactiveRecord #4195

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Oct 25, 2025
Merged

Reduce allocations within ReactiveObject and ReactiveRecord #4195

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
a0df30a
Reduce allocations within ReactiveObject and ReactiveRecord
jl0pd Oct 25, 2025
c0c24e2
Use Volatile.Read for first access
jl0pd Oct 25, 2025
639febf
Merge branch 'main' into reduce-allocations-within-ReactiveObject
glennawatson Oct 25, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
47 changes: 20 additions & 27 deletions src/ReactiveUI/ReactiveObject/ReactiveObject.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -13,42 +13,27 @@ namespace ReactiveUI;
[DataContract]
public class ReactiveObject : IReactiveNotifyPropertyChanged<IReactiveObject>, IHandleObservableErrors, IReactiveObject
{
private readonly Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>> _changing;
private readonly Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>> _changed;
private readonly Lazy<Unit> _propertyChangingEventsSubscribed;
private readonly Lazy<Unit> _propertyChangedEventsSubscribed;
private readonly Lazy<IObservable<Exception>> _thrownExceptions;
private bool _propertyChangingEventsSubscribed;
private bool _propertyChangedEventsSubscribed;

/// <summary>
/// Initializes a new instance of the <see cref="ReactiveObject"/> class.
/// </summary>
public ReactiveObject()
{
_changing = new Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>>(() => ((IReactiveObject)this).GetChangingObservable(), LazyThreadSafetyMode.PublicationOnly);
_changed = new Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>>(() => ((IReactiveObject)this).GetChangedObservable(), LazyThreadSafetyMode.PublicationOnly);
_propertyChangingEventsSubscribed = new Lazy<Unit>(
() =>
{
this.SubscribePropertyChangingEvents();
return Unit.Default;
},
LazyThreadSafetyMode.PublicationOnly);
_propertyChangedEventsSubscribed = new Lazy<Unit>(
() =>
{
this.SubscribePropertyChangedEvents();
return Unit.Default;
},
LazyThreadSafetyMode.PublicationOnly);
_thrownExceptions = new Lazy<IObservable<Exception>>(this.GetThrownExceptionsObservable, LazyThreadSafetyMode.PublicationOnly);
}

/// <inheritdoc/>
public event PropertyChangingEventHandler? PropertyChanging
{
add
{
_ = _propertyChangingEventsSubscribed.Value;
if (!_propertyChangingEventsSubscribed)
{
this.SubscribePropertyChangingEvents();
_propertyChangingEventsSubscribed = true;
}

PropertyChangingHandler += value;
}
remove => PropertyChangingHandler -= value;
Expand All @@ -59,7 +44,12 @@ public event PropertyChangedEventHandler? PropertyChanged
{
add
{
_ = _propertyChangedEventsSubscribed.Value;
if (!_propertyChangedEventsSubscribed)
{
this.SubscribePropertyChangedEvents();
_propertyChangedEventsSubscribed = true;
}

PropertyChangedHandler += value;
}
remove => PropertyChangedHandler -= value;
Expand All @@ -78,7 +68,8 @@ public event PropertyChangedEventHandler? PropertyChanged
[Browsable(false)]
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changing => _changing.Value;
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changing =>
Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, ((IReactiveObject)this).GetChangingObservable(), null) ?? field;

/// <inheritdoc />
[IgnoreDataMember]
Expand All @@ -87,7 +78,8 @@ public event PropertyChangedEventHandler? PropertyChanged
[Browsable(false)]
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changed => _changed.Value;
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changed =>
Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, ((IReactiveObject)this).GetChangedObservable(), null) ?? field;

/// <inheritdoc/>
[IgnoreDataMember]
Expand All @@ -96,7 +88,8 @@ public event PropertyChangedEventHandler? PropertyChanged
[Browsable(false)]
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<Exception> ThrownExceptions => _thrownExceptions.Value;
public IObservable<Exception> ThrownExceptions =>
Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, this.GetThrownExceptionsObservable(), null) ?? field;

/// <inheritdoc/>
void IReactiveObject.RaisePropertyChanging(PropertyChangingEventArgs args) =>
Expand Down
44 changes: 17 additions & 27 deletions src/ReactiveUI/ReactiveObject/ReactiveRecord.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -13,11 +13,8 @@ namespace ReactiveUI;
[DataContract]
public record ReactiveRecord : IReactiveNotifyPropertyChanged<IReactiveObject>, IHandleObservableErrors, IReactiveObject
{
private readonly Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>> _changing;
private readonly Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>> _changed;
private readonly Lazy<Unit> _propertyChangingEventsSubscribed;
private readonly Lazy<Unit> _propertyChangedEventsSubscribed;
private readonly Lazy<IObservable<Exception>> _thrownExceptions;
private bool _propertyChangingEventsSubscribed;
private bool _propertyChangedEventsSubscribed;

/// <summary>
/// Initializes a new instance of the <see cref="ReactiveRecord"/> class.
Expand All @@ -28,31 +25,19 @@ public record ReactiveRecord : IReactiveNotifyPropertyChanged<IReactiveObject>,
#endif
public ReactiveRecord()
{
_changing = new Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>>(() => ((IReactiveObject)this).GetChangingObservable(), LazyThreadSafetyMode.PublicationOnly);
_changed = new Lazy<IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>>>(() => ((IReactiveObject)this).GetChangedObservable(), LazyThreadSafetyMode.PublicationOnly);
_propertyChangingEventsSubscribed = new Lazy<Unit>(
() =>
{
this.SubscribePropertyChangingEvents();
return Unit.Default;
},
LazyThreadSafetyMode.PublicationOnly);
_propertyChangedEventsSubscribed = new Lazy<Unit>(
() =>
{
this.SubscribePropertyChangedEvents();
return Unit.Default;
},
LazyThreadSafetyMode.PublicationOnly);
_thrownExceptions = new Lazy<IObservable<Exception>>(this.GetThrownExceptionsObservable, LazyThreadSafetyMode.PublicationOnly);
}

/// <inheritdoc/>
public event PropertyChangingEventHandler? PropertyChanging
{
add
{
_ = _propertyChangingEventsSubscribed.Value;
if (!_propertyChangingEventsSubscribed)
{
this.SubscribePropertyChangingEvents();
_propertyChangingEventsSubscribed = true;
}

PropertyChangingHandler += value;
}
remove => PropertyChangingHandler -= value;
Expand All @@ -63,7 +48,12 @@ public event PropertyChangedEventHandler? PropertyChanged
{
add
{
_ = _propertyChangedEventsSubscribed.Value;
if (!_propertyChangedEventsSubscribed)
{
this.SubscribePropertyChangedEvents();
_propertyChangedEventsSubscribed = true;
}

PropertyChangedHandler += value;
}
remove => PropertyChangedHandler -= value;
Expand All @@ -83,7 +73,7 @@ public event PropertyChangedEventHandler? PropertyChanged
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changing => // TODO: Create Test
_changing.Value;
Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, ((IReactiveObject)this).GetChangingObservable(), null) ?? field;

/// <inheritdoc />
[IgnoreDataMember]
Expand All @@ -93,7 +83,7 @@ public event PropertyChangedEventHandler? PropertyChanged
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<IReactivePropertyChangedEventArgs<IReactiveObject>> Changed => // TODO: Create Test
_changed.Value;
Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, ((IReactiveObject)this).GetChangedObservable(), null) ?? field;

/// <inheritdoc/>
[IgnoreDataMember]
Expand All @@ -102,7 +92,7 @@ public event PropertyChangedEventHandler? PropertyChanged
[Browsable(false)]
[Display(Order = -1, AutoGenerateField = false, AutoGenerateFilter = false)]
#endif
public IObservable<Exception> ThrownExceptions => _thrownExceptions.Value;
public IObservable<Exception> ThrownExceptions => Volatile.Read(ref field) ?? Interlocked.CompareExchange(ref field, this.GetThrownExceptionsObservable(), null) ?? field;

/// <inheritdoc/>
void IReactiveObject.RaisePropertyChanging(PropertyChangingEventArgs args) => PropertyChangingHandler?.Invoke(this, args);
Expand Down
Loading