v1.4.21 final release notes

[Aaronontheweb]

1.4.21 June 16 2021

Maintenance Release for Akka.NET 1.4

Akka.NET v1.4.21 is a significant release that includes major performance improvements, bug fixes, and a major update to the Akka.DependencyInjection NuGet package.

Performance Improvements
Akka.NET v1.4.21 includes some major performance fixes and improvements:

• Ask is now ~10% faster
• MurmurHash is 33% faster and allocates 0 memory - used heavily in DData, Cluster Sharding, and Consistent Hash Routers
• ActorPath.Parse went from 1672 ns/op to 527 ns/op - a 68% improvement in throughput and a 50% reduction in memory. See #5039 and #5068.
• Akka.Remote: remove ActorPath.ToString call from ResolveActorRefWithLocalAddress
• Important: Revert ThreadPool.SetMinThreads(0,0) - based on the input from users on "Akka.NET v1.4.19: ChannelExecutor performance data"

Our observed performance numbers for Akka.Remote show a significant increase in performance for v1.4.21 over v1.4.20:

Before

PS> dotnet run -c Release --framework netcoreapp3.1      
OSVersion:                         Microsoft Windows NT 6.2.9200.0
ProcessorCount:                    16
ClockSpeed:                        0 MHZ
Actor Count:                       32
Messages sent/received per client: 200000  (2e5)
Is Server GC:                      True
Thread count:                      109

Num clients, Total [msg], Msgs/sec, Total [ms]
         1,  200000,    113379,    1764.56
         5, 1000000,    186429,    5364.05
        10, 2000000,    185340,   10791.11
        15, 3000000,    183218,   16374.06
        20, 4000000,    179824,   22244.63
        25, 5000000,    182716,   27365.89
        30, 6000000,    182039,   32960.61

After

PS> dotnet run -c Release --framework netcoreapp3.1                
OSVersion:                         Microsoft Windows NT 6.2.9200.0 
ProcessorCount:                    16                              
ClockSpeed:                        0 MHZ                           
Actor Count:                       32                              
Messages sent/received per client: 200000  (2e5)                   
Is Server GC:                      True                            
Thread count:                      111                             
                                                                   
Num clients, Total [msg], Msgs/sec, Total [ms]                     
         1,  200000,    109770,    1822.14                         
         5, 1000000,    192902,    5184.79                         
        10, 2000000,    191663,   10435.53                         
        15, 3000000,    191339,   15679.11                         
        20, 4000000,    192725,   20755.78                         
        25, 5000000,    189754,   26350.14                         
        30, 6000000,    189772,   31617.20                         

N.B. these after numbers don't benefit from the performance benefits we observed in v1.4.20 when we invoked ThreadPool.SetMinThreads(0,0), which makes them even more impressive.

Akka.DependencyInjection Updates
We had one major issue we implemented in v1.4.21 for Akka.DependencyInjection: Abstraction of ServiceProvider, Improving Akka.DependencyInjection

What this change did was:

• Deprecate the Akka.DependencyInjection.ServiceProvider class in favor of the Akka.DependencyInjection.DependencyResolver class - to avoid namespace collision with Microsoft.Extensions.DependencyInjection.ServiceProvider;
• Deprecates the Akka.DependencyInjection.ServiceProviderSetup class in favor of the Akka.DependencyInjection.DependencyResolverSetup class for consistency reasons;
• Akka.DependencyInjection.DependencyResolver now takes an input of type IDependencyResolver, which allows users to abstract away the IServiceProvider and mock / replace it during unit testing; and
• Added some non-generic Props methods for dynamically spawning actors via DI.

All of these changes are backwards-compatible with v1.4.20 and earlier - and the deprecation warnings will appear in your code when you upgrade. If you run into any issues upgrading to Akka.DependencyInjection v1.4.21 please reply on this thread!

Other Changes and Fixes

• Akka.Streams: A couple of fixes affecting the FileSubscriber
• Akka.DistributedData: memory leak when recovering events from LMDB data store
• Akka.DistributedData: port VectorClock performance optimizations to VersionVector and similar types

To see the full set of fixes in Akka.NET v1.4.21, please see the milestone on Github.

COMMITS	LOC+	LOC-	AUTHOR
5	34	24	Aaron Stannard
4	196	77	Gregorius Soedharmo
3	3	3	dependabot[bot]
1	2	2	Wessel Kranenborg
1	1	1	Martijn Schoemaker