Akka.NET v1.5.29 introduced an interface change on the IScheduler
that unfortunately caused a lot of other plugins to break due to API compatibility issues. v1.5.30 rolls back that change but still fixes the underlying bug in Akka.Persistence's handling and serialziation of timestamps without any interface changes. v1.5.29 will be deprecated from NuGet.
- DData: Remove Hyperion dependency
- Streams: Fix SelectAsync race condition bug
- Core: Add new IWithTimers API to allow sender override
- Persistence: Fix SnapshotMetadata default timestamp value (DateTimeKind.Utc bug)
- Core: Fix AskTimeoutException message formatting bug
To see the full set of changes in Akka.NET v1.5.30, click here.
3 contributors since release 1.5.28
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
8 | 259 | 104 | Gregorius Soedharmo |
1 | 10 | 10 | Simon Cropp |
1 | 0 | 1 | Aaron Stannard |
Note
Deprecated
This version introduced breaking changes that needs to be reverted. Please use 1.5.30 instead.
Akka.NET v1.5.29 is an emergency patch release that addresses a severe bug for persistence users whom also use protobuf serializer.
- DData: Remove Hyperion dependency
- Streams: Fix SelectAsync race condition bug
- Core: Add new IWithTimers API to allow sender override
- Persistence: Fix SnapshotMetadata default timestamp value (DateTimeKind.Utc bug)
- Core: Fix AskTimeoutException message formatting bug
To see the full set of changes in Akka.NET v1.5.29, click here.
3 contributors since release 1.5.28
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
4 | 177 | 14 | Gregorius Soedharmo |
1 | 10 | 10 | Simon Cropp |
1 | 0 | 1 | Aaron Stannard |
Akka.NET v1.5.28 is a release with several bug fixes and improvements.
- Singleton: Fix oldest member transition log message
- Core: Make ITimeProvider injectable into consuming classes
- Singleton: Fix ClusterSingletonProxy failed to re-acquire singleton actor
- Persistence: Make DateTime.UtcNow the default SnapshotMetadata timestamp
- Remote.TestKit: Improve diagnostics and code modernization
- Persistence.TestKit: Add new ConnectionInterceptor and improve usability
- Sharding: Disable durable DData if RememberEntity does not use DData storage
- Persistence.Sql.Common: Harden journal and snapshot store initialization
- Streams: Fix missing AlsoTo public API in Flow, SubFlow, and Source
- Streams: Fix StreamRefSerializer NRE bug
- Persistence: Fix SnapshotStore.SaveSnapshot metadata timestamp bug
- Persistence.TCK: Add new optional SnapshotStore save data integrity spec
To see the full set of changes in Akka.NET v1.5.28, click here.
2 contributors since release 1.5.27.1
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
10 | 5318 | 5153 | Aaron Stannard |
8 | 1568 | 158 | Gregorius Soedharmo |
Akka.NET v1.5.28-beta1 is a patch beta release with several bug fixes and improvements.
- Singleton: Fix oldest member transition log message
- Core: Make ITimeProvider injectable into consuming classes
- Singleton: Fix ClusterSingletonProxy failed to re-acquire singleton actor
- Persistence: Make DateTime.UtcNow the default SnapshotMetadata timestamp
- Remote.TestKit: Improve diagnostics and code modernization
- Persistence.TestKit: Add new ConnectionInterceptor and improve usability
- Sharding: Disable durable DData if RememberEntity does not use DData storage
- Persistence.Sql.Common: Harden journal and snapshot store initialization
- Streams: Fix missing AlsoTo public API in Flow, SubFlow, and Source
To see the full set of changes in Akka.NET v1.5.28-beta1, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
10 | 5318 | 5153 | Aaron Stannard |
4 | 1440 | 115 | Gregorius Soedharmo |
Akka.NET v1.5.27.1 is a minor patch to fix a race condition between the logging and remoting system.
To see the full set of changes in Akka.NET v1.5.27.1, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 4 | 0 | Aaron Stannard |
1 | 10 | 3 | Gregorius Soedharmo |
Akka.NET v1.5.27 is a significant release that includes new features, mission-critical bug fixes, and some performance improvements.
Major Akka.Cluster.Sharding and Akka.Cluster.Tools.Singleton Bug Fixes
In all prior versions of Akka.NET, there are two high impact distributed systems bugs:
- Akka.Cluster.Tools.Singleton: singleton moves earlier than expected - as soon as new node joins
- Akka.Cluster.Sharding: duplicate shards / entities
As we discovered during the course of our pains-taking bug investigation, these were, in fact, the same issue:
- The
ClusterSingletonManager
is supposed to always belong on the oldest node of a given role type, but an original design error from the time Akka.Cluster.Tools was first introduced to Akka.NET meant that nodes were always sorted in descending order ofUpNumber
. This is backwards: nodes should always be sorted in ascending order ofUpNumber
- this means that the oldest possible node is always at the front of the "who is oldest?" list held by theClusterSingletonManager
. This explains why the singleton could appear to move early during deployments and restarts. - The
ClusterSingletonManager
was suspectible to a race condition where if nodes were shutdown and restarted with the same address in under 20 seconds, the default "down removal margin" used by theClusterSingletonManager
to tolerate dirty exits, it would be possible after multiple successive, fast, restarts for multiple instances of the singleton to be alive at the same time (for a short period.)
Both of these varieties of problem, duplicate singletons, is what lead to duplicate shards.
As a result we've made the following fixes:
- Akka.Cluster.Tools: deprecate ClustersSingletonManagerSettings.ConsiderAppVersion -
AppVersion
is no longer considered for singleton placement as it could easily result in split brains. - Akka.Cluster.Tools: fix mutability and oldest state bugs with
ClusterSingletonManager
- resolves the issue with rapid rolling restarts creating duplicates. We've tested this fix in our test lab across thousands of coordinator restarts and haven't been able to reproduce the issue since (we could easily do it before.) - Akka.Cluster.Tools.Singleton / Akka.Cluster.Sharding: fix duplicate shards caused by incorrect
ClusterSingletonManager
HandOver
- we fixed the member age problem here, which could cause a second singleton to start at inappropriate times.
Akka.Discovery and ClusterClient
Discovery Support
In Akka.NET v1.5.27 we've added support for using Akka.Cluster.Tools.ClusterClient alongside with Akka.Discovery plugins to automatically discover the initial contacts you need for ClusterClientReceptionist
instances in your environment.
You can read the documentation for how this works here: https://getakka.net/articles/clustering/cluster-client.html#contact-auto-discovery-using-akkadiscovery
Related PRs and issues:
- Akka.Discovery: Add multi-config support to config-based discovery
- Cluster.Tools: Fix missing VerboseLogging in ClusterClientSettings.Copy method
- Cluster.Tools: Improve ClusterClientDiscovery to avoid thundering herd problem
- Cluster.Tools: Change ClusterClientDiscovery to use the new Akka.Management "/cluster-client/receptionist" endpoint
Other Bug Fixes and Improvements
- Akka.Cluster: improve gossip serialization performance
- Akka.Streams: Fix
ActorMaterializerImpl
null
LogSource
- Akka.Streams:
AlsoTo
may not be failing graph when its sink throws exception - Akka.DistributedData: if
lmdb.dir
is null or empty, log a warning and set to default
To see the full set of changes in Akka.NET v1.5.27, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
15 | 835 | 1001 | Aaron Stannard |
12 | 1123 | 207 | Gregorius Soedharmo |
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 1 | 1 | Gregorius Soedharmo |
Akka.NET v1.5.27-beta1 improves upon the new ClusterClient initial contact auto-discovery feature to make it more robust in implementation.
- Akka.Discovery: Add multi-config support to config-based discovery
- Cluster.Tools: Fix missing VerboseLogging in ClusterClientSettings.Copy method
- Cluster.Tools: Improve ClusterClientDiscovery to avoid thundering herd problem
- Cluster.Tools: Change ClusterClientDiscovery to use the new Akka.Management "/cluster-client/receptionist" endpoint
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
5 | 422 | 183 | Gregorius Soedharmo |
1 | 4 | 0 | Aaron Stannard |
1 | 1 | 1 | Sean Killeen |
Akka.NET v1.5.26 introduces a new Akka.Cluster.Tools feature and a logging improvement.
Preliminary ClusterClient Initial Contact Auto-Discovery Feature
To use this feature, you will need to use Akka.Discovery implementation (Kubernetes or Azure) version 1.5.26-beta1 or higher
This feature allows ClusterClient to use Akka.Discovery to automatically query for cluster client receptionists inside a dynamic environment such as Kubernetes.
The preliminary documentation for this feature can be read here
You can see the full set of changes for Akka.NET v1.5.26 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
3 | 45 | 11 | Aaron Stannard |
2 | 945 | 15 | Gregorius Soedharmo |
Akka.NET v1.5.25 includes a critical bug fix for logging and some other minor fixes.
Logging Errors Introduced in v1.5.21
Versions [v1.5.21,v1.5.24] are all affected by Akka.Logging: v1.5.21 appears to have truncated log source, timestamps, etc from all log messages - this was a bug introduced when we added the log-filtering feature we shipped in Akka.NET v1.5.21.
This issue has been resolved in v1.5.25 and we've added regression tests to ensure that the log format gets version-checked just like our APIs going forward.
Other fixes:
- Akka.Router: sending a message to a remote actor via
IScheduledTellMsg
results in serialization error - Akka.Discovery: Make Akka.Discovery less coupled with Akka.Management
You can see the full set of changes for Akka.NET v1.5.25 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
6 | 347 | 44 | Aaron Stannard |
2 | 1197 | 1015 | Gregorius Soedharmo |
Akka.NET v1.5.24 is a patch release for Akka.NET that addresses CVE-2018-8292 and also adds a quality of life improvement to IActorRef serialization.
- Fix invalid serializer was being used when serialize-message is set to true
- Add Serialization.DeserializeActorRef() QoL method
- Resolve CVE-2018-8292 in this PR and this PR
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
3 | 35 | 22 | Gregorius Soedharmo |
1 | 26 | 51 | Mike Perrin |
1 | 15 | 2 | Aaron Stannard |
You can see the full set of changes for Akka.NET v1.5.24 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
2 | 299 | 44 | Aaron Stannard |
1 | 47 | 49 | Gregorius Soedharmo |
1 | 1 | 1 | Hassan Abu Bakar |
You can see the full set of changes for Akka.NET v1.5.23 here.
Akka.NET v1.5.22 is a patch release for Akka.NET with a few bug fixes and logging improvement.
- Streams: Bump Reactive.Streams to 1.0.4
- Remote: Bump DotNetty.Handlers to 0.7.6
- Core: Resolve CVE-2018-8292 for Akka.Streams and Akka.Remote
- Core: Expose
BusLogging
EventStream
as public API - Remote: Add cross-platform support to the exception serializer
On Resolving CVE-2018-8292
In order to resolve this CVE, we had to update DotNetty.Handlers
to the latest version and unfortunately, this comes with about 10% network throughput performance hit. We are looking into possible replacement for DotNetty
to improve this performance lost in the future (see #7225
for updates).
Before
Num clients, Total [msg], Msgs/sec, Total [ms], Start Threads, End Threads
1, 200000, 125000, 1600.62, 46, 76
5, 1000000, 494072, 2024.04, 84, 95
10, 2000000, 713013, 2805.73, 103, 107
15, 3000000, 724463, 4141.38, 115, 115
20, 4000000, 714669, 5597.66, 123, 123
25, 5000000, 684932, 7300.37, 131, 107
30, 6000000, 694525, 8639.88, 115, 93
After
Num clients, Total [msg], Msgs/sec, Total [ms], Start Threads, End Threads
1, 200000, 123763, 1616.32, 46, 73
5, 1000000, 386101, 2590.66, 81, 90
10, 2000000, 662691, 3018.54, 98, 104
15, 3000000, 666223, 4503.86, 112, 113
20, 4000000, 669681, 5973.89, 121, 113
25, 5000000, 669255, 7471.86, 121, 105
30, 6000000, 669121, 8967.61, 113, 92
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
6 | 167 | 188 | Aaron Stannard |
3 | 93 | 10 | Gregorius Soedharmo |
You can see the full set of changes for Akka.NET v1.5.22 here.
Akka.NET v1.5.21 is a significant release for Akka.NET with a major feature additions and bug fixes.
- Core: Fix error logging bug
- Core: Add log filtering feature
- Pub-Sub: Fix missing SendOneMessageToEachGroup property
- Core: Fix incorrect IWrappedMessage deserialization when serialize-messages setting is on
- Core: Bump Akka.Analyzers to 0.2.5
Log Message Filtering
You can now filter out unwanted log messages based on either its source or message content. Documentation can be read in the logging documentation.
New Akka.Analyzers Rule
Added AK1006 rule to suggest user to use PersistAll()
and PersistAllAsync()
when applicable. Documentation can be read in the documentation
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
7 | 900 | 53 | Aaron Stannard |
5 | 497 | 1187 | Gregorius Soedharmo |
1 | 1 | 1 | Åsmund |
You can see the full set of changes for Akka.NET v1.5.21 here.
Akka.NET v1.5.20 is a patch release for Akka.NET with a few bug fixes and Akka.Streams quality of life improvement.
- Cluster: Fix split brain resolver downing all nodes when failure detector records are unclean/poisoned
- TestKit: Fix
AkkaEqualException
message formatting - Core: Generate Protobuf code automatically during build
- Streams:
LogSource
quality of life improvement - Core: Fix
HashedWheelTimer
startup crash
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
5 | 360 | 93 | Aaron Stannard |
3 | 187 | 20 | Gregorius Soedharmo |
1 | 81 | 41827 | Yan Pitangui |
You can see the full set of changes for Akka.NET v1.5.20 here.
Akka.NET v1.5.19 is a patch release for Akka.NET with a few bug fixes.
- Persistence.SQLite: Bump Microsoft.Data.SQLite to 8.0.4
- Core: Bump Google.Protobuf to 3.26.1
- Core: Bump Akka.Analyzer to 0.2.4
- Remote: Improve logging
- Cluster: Improve logging
- Core: Fix resource contention problem with HashedWheelTimerScheduler during start-up
- TestKit: Fix async deadlock by replacing IAsyncQueue with System.Threading.Channel
Akka.Analyzers
We've added 3 new analyzer rules to Akka.Analyzers
:
-
AK1004
AK1004 warns users to replace any
ScheduleTellOnce()
andScheduleTellRepeatedly()
invocation inside an actor to implementIWithTimers
interface instead. Documentation can be read here -
AK1005
AK1005 warns users about improper
Sender
andSelf
access from inside an async lambda callbacks inside actor implementation. Documentation can be read here -
AK1007
AK1007 is an error message for any
Timers.StartSingleTimer()
andTimers.StartPeriodicTimer()
invocation from inside the actorPreRestart()
andAroundPreRestart()
lifecycle callback methods. Documentation can be read here
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
9 | 366 | 1951 | Aaron Stannard |
9 | 14 | 14 | dependabot[bot] |
2 | 516 | 30 | Gregorius Soedharmo |
You can see the full set of changes for Akka.NET v1.5.19 here.
Akka.NET v1.5.18 is a patch release for Akka.NET with a feature addition.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 9 | 9 | Aaron Stannard |
1 | 1 | 1 | dependabot[bot] |
You can see the full set of changes for Akka.NET v1.5.18 here.
Akka.NET v1.5.17.1 is a patch release for Akka.NET with a bug fix.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 1 | 1 | Gregorius Soedharmo |
1 | 1 | 1 | Aaron Stannard |
Akka.NET v1.5.17 is a patch release for Akka.NET with some feature additions and bug fixes.
- Core: Fix null ref for
LogSource
- Persistence.TCK: Make all snapshot tests virtual
- Core: Suppress extremely verbose
TimerScheduler
debug message - Sharding: Implement reliable delivery custom message bypass feature
- Update dependencies
- Documentations
Akka.Analyzers
- The AK1001 rule has been removed due to the discussion here.
- AK1002 has been enhanced with better problem detection.
You can see the full set of changes for Akka.NET v1.5.17 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
7 | 1342 | 732 | Gregorius Soedharmo |
4 | 5 | 5 | dependabot[bot] |
3 | 158 | 4 | Aaron Stannard |
2 | 3 | 3 | hassan-me |
1 | 2 | 8 | Massimiliano Donini |
1 | 12 | 12 | Mattias Jakobsson |
Akka.NET v1.5.16 is a patch release for Akka.NET with some feature additions and changes.
- Core: Bump Google.Protobuf to 3.25.2
- Core: Remove redundant assembly titles
- Akka.Cluster.Sharding: Fix sharding entity ID extractor nullability
- Akka.Cluster.Sharding: Fix cluster sharding benchmark
- Akka.TestKit: Fix Watch and Unwatch bug
- Akka.Cluster.Metrics: Separate business models and wire format models
- Akka.Analyzer: Bump Akka.Analyzer to 0.2.2
Akka.Analyzers
We have expanded Akka.Analyzer and introduced 2 new rules to the Roslyn analyzer:
AK1002
: Error: Must not awaitSelf.GracefulStop()
insideReceiveAsync<T>()
orReceiveAnyAsync
AK1003
: Warning:ReceiveAsync<T>()
orReceiveAnyAsync()
message handler without async lambda body
See the full set of supported Akka.Analyzers rules here
You can see the full set of changes for Akka.NET v1.5.16 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
6 | 1268 | 628 | Gregorius Soedharmo |
5 | 6 | 6 | dependabot[bot] |
2 | 286 | 224 | Aaron Stannard |
1 | 2120 | 0 | Yan Pitangui |
1 | 2 | 2 | Mattias Jakobsson |
1 | 2 | 0 | Ebere Abanonu |
1 | 0 | 65 | Simon Cropp |
Akka.NET v1.5.15 is a significant release for Akka.NET with some major feature additions and changes.
- Introducing
Akka.Analyzers
- Roslyn Analysis for Akka.NET - Akka.Cluster.Sharding: perf optimize message extraction, automate
StartEntity
andShardEnvelope
handling - Akka.Cluster.Tools: Make
ClusterClient
messages be serialized usingClusterClientMessageSerializer
- Akka.Persistence: Fix
LocalSnapshotStore
Metadata Fetch to ensure persistenceid match. - Akka.Delivery: Fix
ProducerControllerImpl<T>
state bug - Change MS.EXT and System package versioning to range - we now support all Microsoft.Extensions packages from
(6.0,]
. - Akka.Serialization:
INoSerializationVerificationNeeded
does not handleIWrappedMessage
correctly
Akka.Analyzers
The core Akka NuGet package now references Akka.Analyzers, a new set of Roslyn Code Analysis and Code Fix Providers that we distribute via NuGet. You can see the full set of supported Akka.Analyzers rules here.
Akka.Cluster.Sharding Changes
In #6863 we made some major changes to the Akka.Cluster.Sharding API aimed at helping improve Cluster.Sharding's performance and ease of use. However, these changes may require some effort on the part of the end user in order to take full advantage:
ExtractEntityId
andExtractShardId
have been deprecated as they fundamentally can't be extended and can't benefit from the performance improvements introduced into Akka.NET v1.5.15. It is imperative that you migrate to using theHashCodeMessageExtractor
instead.- You no longer need to handle
ShardRegion.StartEntity
orShardingEnvelope
inside yourIMessageExtractor
implementations, and in factAK2001
(part of Akka.Analyzers) will automatically detect this and remove those handlers for you. Akka.NET automatically handles these two message types internally now.
ClusterClient Serialization Changes
In #7032 we solved a long-standing serialization problem with the ClusterClient
where Send
, SendToAll
, and Publish
were not handled by the correct internal serializer. This has been fixed by default in Akka.NET v1.5.15, but this can potentially cause wire compatibility problems during upgrades - therefore we have introduced a configuration setting to toggle this:
# re-enable legacy serialization
akka.cluster.client.use-legacy-serialization = on
That setting is currently set to on
by default, so v1.5.15 will still behave like previous versions of Akka.NET. However, if you have been affected by serialization issues with the ClusterClient
(such as #6803) you should toggle this setting to off
.
See "Akka.NET v1.5.15 Upgrade Advisories" for full details on some of the things you might need to do while upgrading to this version of Akka.NET.
You can see the full set of changes for Akka.NET v1.5.15 here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
16 | 2228 | 1490 | Aaron Stannard |
9 | 9 | 9 | dependabot[bot] |
2 | 610 | 173 | Gregorius Soedharmo |
2 | 337 | 0 | Drew |
2 | 124 | 118 | Lehonti Ramos |
1 | 2 | 2 | Sergey Popov |
1 | 108 | 25 | Yaroslav Paslavskiy |
1 | 1 | 1 | Bert Lamb |
Akka.NET v1.5.14 is a maintenance release with several bug fixes.
- Streams: Ensure stream are closed on shutdown
- Akka: Fix PeriodicTimer HashWheelTimerScheduler deadlock during start
- Cluster: Old version of LeastShardAllocationStrategy is now deprecated
- Query: Add a more descriptive ToString() values to Offset types
- Package dependency upgrades
If you want to see the full set of changes made in Akka.NET v1.5.14, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
11 | 25 | 21 | dependabot[bot] |
3 | 14 | 2 | Aaron Stannard |
3 | 114 | 369 | Simon Cropp |
2 | 36 | 31 | Gregorius Soedharmo |
1 | 41 | 43 | Lehonti Ramos |
1 | 38 | 0 | Yaroslav Paslavskiy |
1 | 3 | 0 | Sean Killeen |
1 | 227 | 25 | Drew |
1 | 1 | 1 | szaliszali |
Akka.NET v1.5.13 is a maintenance release with several bug fixes and also performance and QOL improvements.
- Akka: Clean up and optimize actor name validation
- Akka: Wrap all scheduler Tell messages in
IScheduledMessage
envelope - Akka: Fix possible NRE bug in
Dispatchers
- Akka.Cluster.Sharding: Log shard coordinator remember entities timeout
- Akka.Cluster.Sharding: Fix shard coordinator throwing NullReferenceException
- Akka.Streams: Log errors inside SelectAsync stage
- Akka.Streams: Add supervisor strategy support for Throttle stage
- Akka: Change HashedWheelTimerScheduler implementation to use
PeriodicTimer
for net6.0+ builds - Package dependency upgrades
If you want to see the full set of changes made in Akka.NET v1.5.13, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
18 | 25 | 25 | dependabot[bot] |
6 | 435 | 200 | Gregorius Soedharmo |
4 | 512 | 293 | Aaron Stannard |
2 | 3 | 7 | Simon Cropp |
1 | 7 | 0 | Sergey Popov |
1 | 66 | 17 | Ismael Hamed |
1 | 1 | 1 | HamzaAmjad-RG |
Akka.NET v1.5.13-beta1 is a maintenance release with several performance and QOL improvements.
- Akka.Cluster.Sharding: Log shard coordinator remember entities timeout
- Akka.Cluster.Sharding: Fix shard coordinator throwing NullReferenceException
- Akka.Streams: Log errors inside SelectAsync stage
- Akka.Streams: Add supervisor strategy support for Throttle stage
- Akka: Change HashedWheelTimerScheduler implementation to use
PeriodicTimer
for net6.0+ builds - Package dependency upgrades
If you want to see the full set of changes made in Akka.NET v1.5.13-beta1, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
11 | 15 | 15 | dependabot[bot] |
3 | 302 | 143 | Aaron Stannard |
2 | 384 | 195 | Gregorius Soedharmo |
1 | 7 | 0 | Sergey Popov |
1 | 66 | 17 | Ismael Hamed |
1 | 3 | 5 | Simon Cropp |
1 | 1 | 1 | HamzaAmjad-RG |
Akka.NET v1.5.12 is a maintenance release with a minor API change and a minor bug fix.
- Persistence.Query: Fix
ReadJournalFor()
thread safety - Persistence.Query: Expose new
Tags
property inEventEnvelope
- Documentation: Fix typo in member-roles.md
If you want to see the full set of changes made in Akka.NET v1.5.12, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
5 | 34 | 18 | Aaron Stannard |
2 | 150 | 51 | Gregorius Soedharmo |
1 | 1 | 1 | dependabot[bot] |
1 | 1 | 1 | Jim Aho |
Akka.NET v1.5.11 is a maintenance release with a minor API change and internal code modernization/cleanup.
- Remote: Modernize DotNettyTransportSettings class and add support for a SSL Setup class
- PubSub: Make CountSubscriber query command public
If you want to see the full set of changes made in Akka.NET v1.5.11, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 465 | 321 | Gregorius Soedharmo |
1 | 22 | 2 | Aaron Stannard |
Akka.NET v1.5.10 is a maintenance release with a minor API change.
If you want to see the full set of changes made in Akka.NET v1.5.10, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 70 | 12 | Gregorius Soedharmo |
Akka.NET v1.5.9 is a maintenance release that introduces some performance improvements and internal code cleanup/modernization.
Changes:
Improvements:
- Memory optimization, use
Array.Empty
instead of creating empty arrays - Remoting: Log all wrapped message layers during errors
- Port #6805 and #6807, Improve Stream and Pattern.Backoff instance creation time performance
- DData: Harden LWWDictionary serialization null check
Code modernization:
Update dependency versions:
- Bump Google.Protobuf to 3.23.4
- Bump Akka.MultiNode.TestAdapter to 1.5.8
- Bump Microsoft.Data.SQLite to 7.0.9
- Bump Microsoft.Extensions.ObjectPool to 7.0.8
- Bump Xunit to 2.5.0
Akka.TestKit.Xunit Changes
Due to breaking API change in Xunit 2.5.0, updating to Akka.NET 1.5.9 might break your unit tests. Some of the breaking change that we've noticed are:
AkkaEqualException
constructor has been changed due to changes in Xunit API. If you're using this class, please use theAkkaEqualException.ForMismatchedValues()
static method instead of using the constructor.- Testing for exception types by calling async code inside a sync delegate will not unwrap the
AggregateException
thrown. Either use async all the way or manually unwrap the exception. - Xunit
Asset.Equal()
does not automatically check for collection item equality anymore, that means doingAssert.Equal()
between two dictionary or list would not work anymore. - Some Xunit classes have been changed from public to private. If you're using these classes, you will need to refactor your code.
- FsCheck.Xunit: Xunit Roslyn analyzer has become a bit too overzealous and insists that all unit test method can only return either void or Task and will raise a compilation error if you tried to return anything else. If you're using
FsCheck.Xunit
, you will need to use a pragma to disable this check:#pragma warning disable xUnit1028
.
If you want to see the full set of changes made in Akka.NET v1.5.9, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
12 | 171 | 155 | dependabot[bot] |
7 | 466 | 165 | Aaron Stannard |
4 | 1648 | 1725 | Simon Cropp |
1 | 9 | 4 | Gregorius Soedharmo |
1 | 7 | 1 | Michael Buck |
Akka.NET v1.5.8 is a maintenance release that introduces some new features and fixes some bugs with Akka.NET v1.5.7 and earlier.
- Akka.Streams: Added
Source
/Flow
Setup
operator - Akka.Cluster.Sharding: fixed potential wire format problem when upgrading from v1.4 to v1.5 with
state-store-mode=ddata
andremember-entities=on
- Akka.Remote.TestKit: Fix MNTR crashing because it is using PolyFill extension method
If you want to see the full set of changes made in Akka.NET v1.5.8, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
9 | 11 | 11 | dependabot[bot] |
2 | 8 | 0 | Aaron Stannard |
2 | 75 | 4 | Gregorius Soedharmo |
2 | 132 | 158 | Simon Cropp |
1 | 431 | 1 | Ismael Hamed |
1 | 1 | 1 | Andrea Di Stefano |
Akka.NET v1.5.7 is a significant release that introduces a major new reliable message delivery feature to Akka.NET and Akka.Cluster.Sharding: Akka.Delivery
.
Akka.Delivery
Akka.Delivery is a reliable delivery system that leverages built-in actors, serialization, and persistence to help guarantee that all messages sent from one producer to one consumer will be delivered, in-order, even across process restarts / actor restarts / network outages.
Akka.Delivery's functionality is divded across four libraries:
- Akka - defines the base definitions for all messages, the
ProducerController
type, and theConsumerController
type; - Akka.Cluster - contains the serialization definitions for Akka.Delivery;
- Akka.Persistence - contains the
EventSourcedProducerQueue
implementation, an optional feature that can be used to make theProducerController
's outbound delivery queue persisted to the Akka.Persistence Journal and SnapshotStore; and - Akka.Cluster.Sharding - contains the definitions for the
ShardingProducerController
andShardingConsumerController
.
We've documented how these features work in the following two detailed articles official website:
If you want to see the full set of changes made in Akka.NET v1.5.7, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
9 | 13972 | 135 | Aaron Stannard |
6 | 92 | 88 | Ebere Abanonu |
4 | 803 | 807 | Simon Cropp |
3 | 70 | 53 | Gregorius Soedharmo |
3 | 3 | 3 | dependabot[bot] |
Version 1.5.6 is a patch with a few minor bug fix
- TestKit: Remove duplicate info log for unhandled messages
- Core: Change logging DateTime formatter from 12 hour to 24 hour format
If you want to see the full set of changes made in Akka.NET v1.5.6, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
2 | 4 | 4 | Aaron Stannard |
2 | 33 | 84 | Simon Cropp |
2 | 2 | 2 | dependabot[bot] |
2 | 2 | 2 | Richard Smith |
1 | 2 | 2 | Gregorius Soedharmo |
1 | 2 | 12 | Sergey Popov |
- TestKit: Add new variant of
ExpectAll
that accepts predicates - FSharp: Downgrade FSharp to v6.0.5
- Core: Bump Google.Protobuf from 3.22.1 to 3.22.3
- Core: Fix ByteString to check for index bounds
- Core: Fix ReceiveActor ReceiveAsync ReceiveTimeout bug
- Core: Fix race condition inside FastLazy
If you want to see the full set of changes made in Akka.NET v1.5.5, click here.
7 contributors since release 1.5.4
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
16 | 68 | 34 | Ebere Abanonu |
9 | 598 | 1053 | Simon Cropp |
4 | 4 | 4 | dependabot[bot] |
2 | 229 | 5 | Gregorius Soedharmo |
1 | 33 | 28 | Aaron Stannard |
1 | 256 | 3 | Malcolm Learner |
1 | 148 | 140 | Sergey Popov |
IStash Enhancements
IStash
API have been improved with metrics API and its bound/capacity can be programatically set. Documentation can be read here
If you want to see the full set of changes made in Akka.NET v1.5.4, click here.
5 contributors since release 1.5.3
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
7 | 477 | 486 | Ebere Abanonu |
4 | 627 | 143 | Aaron Stannard |
2 | 2 | 2 | dependabot[bot] |
1 | 87 | 0 | Sergey Popov |
1 | 0 | 1 | Gregorius Soedharmo |
- Persistence.Sqlite: Bump Microsoft.Data.SQLite to 7.0.5
- Serialization.Hyperion: Fix bug: surrogate and known type provider not applied correctly by Setup
- Akka: Bump Microsoft.Extensions.ObjectPool to 7.0.5
- Persistence.Sql.Common: Add transaction isolation level to SQL queries
SQL Transaction Isolation Level Setting
In 1.5.3, we're introducing fine-grained control over transaction isolation level inside the Akka.Persistence.Sql.Common
common library. This setting will be propagated to the rest of the SQL persistence plugin ecosystem and the Akka.Hosting
package in their next release version.
Four new HOCON settings are introduced:
akka.persistence.journal.{plugin-name}.read-isolation-level
akka.persistence.journal.{plugin-name}.write-isolation-level
akka.persistence.snapshot-store.{plugin-name}.read-isolation-level
akka.persistence.snapshot-store.{plugin-name}.write-isolation-level
you can go to the official Microsoft documentation to read more about these isolation level settings.
If you want to see the full set of changes made in Akka.NET v1.5.3, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
23 | 1284 | 1248 | Ebere Abanonu |
4 | 7 | 7 | dependabot[bot] |
3 | 933 | 267 | Gregorius Soedharmo |
2 | 4498 | 4407 | Aaron Stannard |
There are some major behavioral changes introduced to Akka.Cluster and Akka.Persistence in Akka.NET v1.5.2 - to learn how these changes might affect your Akka.NET applications, please see our Akka.NET v1.5.2 Upgrade Advisories on the Akka.NET website.
- Akka.Remote: Remove secure cookie from configuration
- DData: Remove unused _pruningPerformed and _tombstonedNodes variables
- Akka.Persistence: Remove default object serializer in Sql.Common
- Akka.Cluster: Log send time in verbose heartbeat message
- Akka.Streams: Optimize ForEachAsync
- Akka: Implement alternative AtomicState leveraging WaitAsync
- Akka.Streams: Use correct capacity when creating DynamicQueue when FixedQueue is full
- Akka.Cluster: Enable keep majority split brain resolver as default
If you want to see the full set of changes made in Akka.NET v1.5.2, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
56 | 2580 | 2913 | Ebere Abanonu |
5 | 201 | 82 | Aaron Stannard |
4 | 754 | 558 | Ismael Hamed |
3 | 4 | 4 | dependabot[bot] |
2 | 33 | 12 | Sergey Popov |
1 | 511 | 53 | Gregorius Soedharmo |
1 | 1 | 1 | ondravondra |
1 | 0 | 2 | Simon Cropp |
- Akka.Persistence: Improve memory allocation
- Akka.Persistence: Implement persistence query in InMemory journal
- Akka: Fix bugs reported by PVS-Studio static analysis
- Akka: Bump Google.Protobuf to 3.22.1
- Akka.Persistence.Sqlite: Bump Microsoft.Data.SQLite to 7.0.4
- Akka: Fix StackOverflow exception in NewtonSoftSerializer
If you want to see the full set of changes made in Akka.NET v1.5.1, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
9 | 425 | 331 | Ebere Abanonu |
5 | 6 | 6 | dependabot[bot] |
3 | 2399 | 109 | Sergey Popov |
1 | 97 | 4 | Gregorius Soedharmo |
1 | 2 | 2 | Aaron Stannard |
Version 1.5.0 is a major new release of Akka.NET that is now marked as stable and ready for production use.
You can read the full notes about what's changed in Akka.NET v1.5 here. We also encourage you to watch our video: "Akka NET v1.5 New Features and Upgrade Guide"
If you want to see the full set of changes made in Akka.NET v1.5.0 so far, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
95 | 25041 | 24976 | Gregorius Soedharmo |
85 | 89784 | 18362 | Aaron Stannard |
76 | 95 | 95 | dependabot[bot] |
18 | 3201 | 908 | Ismael Hamed |
5 | 230 | 251 | Sergey Popov |
2 | 77 | 7 | Vagif Abilov |
2 | 38 | 8 | Brah McDude |
1 | 92 | 92 | nabond251 |
1 | 843 | 0 | Drew |
1 | 7 | 6 | Tjaart Blignaut |
1 | 5 | 4 | Sean Killeen |
1 | 32 | 1 | JonnyII |
1 | 26 | 4 | Thomas Stegemann |
1 | 203 | 5 | Ebere Abanonu |
1 | 2 | 2 | Popov Sergey |
1 | 2 | 2 | Denis |
1 | 16 | 0 | Damian |
1 | 11 | 2 | Nicolai Davies |
1 | 101 | 3 | aminchenkov |
1 | 1 | 1 | zbynek001 |
1 | 1 | 1 | Michel van Os |
1 | 1 | 1 | Adrian D. Alvarez |
Version 1.5.0-beta5 contains breaking API changes and new API changes for Akka.NET.
- Akka.Cluster: Remove
JoinAsync
andJoinSeedNodesAsync
default timeout values - Akka.Event: expose
Args()
onLogMessage
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
2 | 50 | 28 | Aaron Stannard |
1 | 22 | 32 | Gregorius Soedharmo |
Version 1.5.0-beta4 contains breaking API changes and new API changes for Akka.NET.
- Akka.Persistence.TCK: remove
IDisposable
from Akka.Persistence.TCK - this hid methods from theTestKit
base classes. - Akka.Remote: Make transport adapter messages public - adds back public APIs from v1.4.
- Akka.TestKit: fix accidental breaking changes in v1.5.0-beta3
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
2 | 110 | 37 | Aaron Stannard |
1 | 253 | 7 | Gregorius Soedharmo |
Version 1.5.0-beta3 contains breaking API changes and new API changes for Akka.NET.
- Removed a number of
Obsolete
APIs that were generally not used much. - Akka.Actor:
ActorSystem.Create
throwsPlatformNotSupportedException
on net7.0-android - Akka.Actor: Append message content to
DeadLetter
log messages - Akka.Streams: Use
ActorSystem
forMaterializer
- massive memory improvements for applications that materialize a large number of streams. - Akka.Persistence.Query.Sql: backpressure control for queries - full details on this here: https://petabridge.com/blog/largescale-cqrs-akkadotnet-v1.5/
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
14 | 68 | 794 | Gregorius Soedharmo |
5 | 997 | 498 | Aaron Stannard |
3 | 6 | 6 | dependabot[bot] |
Version 1.5.0-beta2 contains breaking API changes and new API changes for Akka.NET.
- Akka.Event: Add K to the DateTime format string to include TZ information
- Akka.TestKit: Reintroduce old code and mark them obsolete - fixes major regression in Akka.TestKit.Xunit2 where we removed
IDipsoable
before. This PR reintroduces it for backwards compat. - Akka.Cluster.Sharding: clean its internal cache if region/proxy died
- Akka.Util: Harden
Option<T>
by disallowing null value - Akka.Util: move
DateTime
/TimeSpan
extension APIs out of Akka.Util and into Akka.Cluster.Metrics - Akka.Util: Remove unsafe
implicit
conversion operators inAtomicBoolean
andAtomicReference<T>
- Akka: Standardize on C# 11.0
- Akka.Persistence: improve
AsyncWriteJournal
andPersistentActor
performance
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
8 | 260 | 942 | Aaron Stannard |
5 | 169 | 60 | Gregorius Soedharmo |
Version 1.5.0-beta1 contains breaking API changes and new API changes for Akka.NET.
Breaking Changes: Logging
In #6408 the entire ILoggingAdapter
interface was rewritten in order to improve extensibility and performance (logging is now 30-40% faster in all cases and allocates ~50% fewer objects for large format strings).
All of the changes made here are source compatible, but not binary compatible - meaning that users and package authors will need to do the following:
- Add
using Akka.Event
in all files that used theILoggingAdapter
and - Recompile.
NOTE: you can use a
global using Akka.Event
directive to do this solution / project-wide if your project supports C# 10 and / or .NET 6.
In addition to improving the performance of the ILoggingAdapter
system, we've also made it more extensible - for instance, you can now globally configure the ILogMessageFormatter
via the following HOCON:
akka {
loglevel=INFO,
loggers=["Akka.Logger.Serilog.SerilogLogger, Akka.Logger.Serilog"]
logger-formatter="Akka.Logger.Serilog.SerilogLogMessageFormatter, Akka.Logger.Serilog"
}
That will allow users to use the SerilogLogMessageFormatter
globally throughout their applications - no more annoying calls like this inside individual actors that want to use semantic logging:
private readonly ILoggingAdapter _logger = Context.GetLogger<SerilogLoggingAdapter>();
Breaking Changes: Akka.Persistence.Sql.Common
This is a breaking change that should effect almost no users, but we deleted some old, bad ideas from the API surface and it might require all Akka.Persistence.Sql* plugins to be recompiled.
For what it's worth, Akka.Persistence.Sql.Common's performance has been improved significantly and we'll continue working on that with some additional API changes this week.
Other Changes and Additions
- Akka.Actor: New API -
IActorRef.WatchAsync
- adds a new extension method toIActorRef
which allows users to subscribe to actor lifecycle notifications outside of theActorSystem
. - Akka.Actor: Suppress
System.Object
warning for serializer configuration changes
If you want to see the full set of changes made in Akka.NET v1.5.0 so far, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
12 | 15 | 15 | dependabot[bot] |
11 | 1930 | 1278 | Aaron Stannard |
2 | 143 | 73 | Sergey Popov |
1 | 26 | 4 | Thomas Stegemann |
1 | 1 | 1 | Michel van Os |
Version 1.5.0-alpha3 contains several bug fixes and new features to Akka.NET
- Akka.TestKit: Remove Akka.Tests.Shared.Internal dependency
- Akka.TestKit: Added ReceiveAsync feature to TestActorRef
- Akka.Stream: Fix
IAsyncEnumerator.DisposeAsync
bug - Akka: Add
Exception
serialization support for built-in messages - Akka: Add simple actor telemetry feature
- Akka.Streams: Move Channel stages from Alpakka to Akka.NET repo
- Akka: Set actor stash capacity to actor mailbox or dispatcher size
- Akka: Add
ByteString
support to copy to/fromMemory
andSpan
- Akka: Add support for
UnrestrictedStash
- Akka: Add API for
UntypedActorWithStash
- Akka.Persistence.Sql.Common: Fix unhandled
DbExceptions
that are wrapped insideAggregateException
- Akka.Persistence.Sql: Fix persistence id publisher actor hung on failure messages
- Akka: Change default pool router supervisor strategy to
Restart
- NuGet package upgrades:
If you want to see the full set of changes made in Akka.NET v1.5.0 so far, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
27 | 30 | 30 | dependabot[bot] |
11 | 2212 | 165 | Gregorius Soedharmo |
4 | 741 | 208 | Ismael Hamed |
4 | 680 | 112 | Aaron Stannard |
3 | 87 | 178 | Sergey Popov |
1 | 843 | 0 | Drew |
1 | 2 | 2 | Popov Sergey |
Akka.NET v1.5.0-alpha3 is a security patch for Akka.NET v1.5.0-alpha2 but also includes some other fixes.
Security Advisory: Akka.NET v1.5.0-alpha2 and earlier depend on an old System.Configuration.ConfigurationManager version 4.7.0 which transitively depends on System.Common.Drawing v4.7.0. The System.Common.Drawing v4.7.0 is affected by a remote code execution vulnerability GHSA-ghhp-997w-qr28.
We have separately created a security advisory for Akka.NET Versions < 1.4.46 and < 1.5.0-alpha3 to track this issue.
Fixes and Updates
- Akka: Revert ConfigurationException due to binary incompatibility
- Akka: Upgrade to Newtonsoft.Json 13.0.1 as minimum version - resolves security issue.
- Akka: Upgrade to System.Configuration.ConfigurationManager 6.0.1 - resolves security issue.
- Akka: Upgrade to Google.Protobuf 3.21.9
- Akka.Cluster.Tools: Make sure that
DeadLetter
s published byDistributedPubSubMediator
contain full context of topic - Akka.Streams: Remove suspicious code fragment in ActorMaterializer
- Akka.IO: Report cause for Akka/IO TCP
CommandFailed
events - Akka.Cluster.Metrics: Improve CPU/Memory metrics collection at Akka.Cluster.Metrics - built-in metrics are now much more accurate.
You can see the full set of tracked issues for Akka.NET v1.5.0 here.
Akka.NET v1.5.0-alpha2 is a maintenance release for Akka.NET v1.5 that contains numerous performance improvements in critical areas, including core actor message processing and Akka.Remote.
Performance Fixes
- remove delegate allocation from
ForkJoinDispatcher
andDedicatedThreadPool
- eliminate
Mailbox
delegate allocations - Reduce
FSM<TState, TData>
allocations - removed boxing allocations inside
FSM.State.Equals
- Eliminate
DefaultLogMessageFormatter
allocations
In sum you should expect to see total memory consumption, garbage collection, and throughput improve when you upgrade to Akka.NET v1.5.0-alpha2.
Other Features and Improvements
- DData: Suppress gossip message from showing up in debug log unless verbose debug logging is turned on
- TestKit: TestKit automatically injects the default TestKit default configuration if an ActorSystem is passed into its constructor
- Sharding: Added a new
GetEntityLocation
query message to retrieve an entity address location in the shard region - Sharding: Fixed
GetEntityLocation
uses wrong actor path - Akka.Cluster and Akka.Cluster.Sharding: should throw human-friendly exception when accessing cluster / sharding plugins when clustering is not running
- Akka.Cluster.Sharding: Add
HashCodeMessageExtractor
factory - Akka.Persistence.Sql.Common: Fix
DbCommand.CommandTimeout
inBatchingSqlJournal
Akka.NET v1.5.0-alpha1 is a major release that contains a lot of code improvement and rewrites/refactors. Major upgrades to Akka.Cluster.Sharding in particular.
Deprecation
Some codes and packages are being deprecated in v1.5
- Deprecated/removed Akka.DI package
Please use the new
Akka.DependencyInjection
NuGet package as a replacement. Documentation can be read here - Deprecated/removed Akka.MultiNodeTestRunner package
Please use the new
Akka.MultiNode.TestAdapter
NuGet package as a replacement. Documentation can be read here. - [Streams] Refactor
SetHandler(Inlet, Outlet, IanAndOutGraphStageLogic)
toSetHandlers()
Changes
Akka
- Add dual targetting to support .NET 6.0
All
Akka.NET
packages are now dual targetting netstandard2.0 and net6.0 platforms, we will be integrating .NET 6.0 better performing API and SDK in the future. - Add
IThreadPoolWorkItem
support toThreadPoolDispatcher
- Add
ValueTask
support toPipeTo
extensions - Add
CancellationToken
support toCancelable
- Fix long starting loggers crashing
ActorSystem
startup All loggers are asynchronously started duringActorSystem
startup. A warning will be logged if a logger does not respond within the prescribedakka.logger-startup-timeout
period and will be awaited upon in a detached task until theActorSystem
is shut down. This have a side effect in that slow starting loggers might not be able to capture all log events emmited by theEventBus
until it is ready.
Akka.Cluster
- Fix
ChannelTaskScheduler
to work with Akka.Cluster, ported from 1.4 - Harden
Cluster.JoinAsync()
andCluster.JoinSeedNodesAsync()
methods - Fix
ShardedDaemonProcess
should use lease, if configured - Make
SplitBrainResolver
more tolerant to invalid node records - Enable
Heartbeat
andHearbeatRsp
message serialization and deserialization By default,Akka.Cluster
will now use the newHeartbeat
andHartbeatRsp
message serialization/deserialization that was introduced in version 1.4.19. If you're doing a rolling upgrade from a version older than 1.4.19, you will need to setakka.cluster.use-legacy-heartbeat-message
to true.
Akka.Cluster.Sharding
- Make Cluster.Sharding recovery more tolerant against corrupted persistence data
- Major reorganization to Akka.Cluster.Sharding
The Akka.Cluster.Sharding changes in Akka.NET v1.5 are significant, but backwards compatible with v1.4 and upgrades should happen seamlessly.
Akka.Cluster.Sharding's state-store-mode
has been split into two parts:
- CoordinatorStore
- ShardStore
Which can use different persistent mode configured via akka.cluster.sharding.state-store-mode
& akka.cluster.sharding.remember-entities-store
.
Possible combinations:
state-store-mode | remember-entities-store | CoordinatorStore mode | ShardStore mode |
---|---|---|---|
persistence (default) | - (ignored) | persistence | persistence |
ddata | ddata | ddata | ddata |
ddata | eventsourced (new) | ddata | persistence |
There should be no breaking changes from user perspective. Only some internal messages/objects were moved.
There should be no change in the PersistentId
behavior and default persistent configuration (akka.cluster.sharding.state-store-mode
)
This change is designed to speed up the performance of Akka.Cluster.Sharding coordinator recovery by moving remember-entities
recovery into separate actors - this also solves major performance problems with the ddata
recovery mode overall.
The recommended settings for maximum ease-of-use for Akka.Cluster.Sharding going forward will be:
akka.cluster.sharding{
state-store-mode = ddata
remember-entities-store = eventsourced
}
However, for the sake of backwards compatibility the Akka.Cluster.Sharding defaults have been left as-is:
akka.cluster.sharding{
state-store-mode = persistence
# remember-entities-store (not set - also uses legacy Akka.Persistence)
}
Switching over to using remember-entities-store = eventsourced
will cause an initial migration of data from the ShardCoordinator
's journal into separate event journals going forward - this migration is irreversible without taking the cluster offline and deleting all Akka.Cluster.Sharding-related data from Akka.Persistence, so plan accordingly.
Akka.Cluster.Tools
- Add typed
ClusterSingleton
support - Singleton can use
Member.AppVersion
metadata to decide its host node during hand-overAkka.Cluster.Singleton
can useMember.AppVersion
metadata when it is relocating the singleton instance. When turned on, new singleton instance will be created on the oldest node in the cluster with the highestAppVersion
number. You can opt-in to this behavior by settingakka.cluster.singleton.consider-app-version
to true.
Akka.Persistence.Query
Akka.Remote
- Fix typo in HOCON SSL settings. Backward compatible with the old setting names
- Treat all exceptions thrown inside
EndpointReader
message dispatch as transient, Ported from 1.4 - Fix SSL enable HOCON setting
Akka.Streams
- Allow GroupBy sub-flow to re-create closed sub-streams, backported to 1.4
- Fix ActorRef source not completing properly, backported to 1.4
- Rewrite
ActorRefSink
as aGraphStage
- Add stream cancellation cause upstream propagation, ported from 1.4
- Fix
VirtualProcessor
subscription bug, ported from 1.4 - Refactor
Sink.Ignore
signature fromTask
toTask<Done>
- Add
SourceWithContext.FromTuples()
operator` - Add
GroupedWeightedWithin
operator - Add
IAsyncEnumerable
source
Akka.TestKit
Akka.NET v1.4.37 is a minor release that contains some minor bug fixes.
- Persistence.Query: Change AllEvents query failure log severity from Debug to Error
- Coordination: Harden LeaseProvider instance Activator exception handling
- Akka: Make ActorSystemImpl.Abort skip the CoordinatedShutdown check
If you want to see the full set of changes made in Akka.NET v1.4.37, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
3 | 15 | 4 | Gregorius Soedharmo |
1 | 2 | 2 | dependabot[bot] |
Akka.NET v1.4.36 is a minor release that contains some bug fixes. Most of the changes have been aimed at improving our web documentation and code cleanup to modernize some of our code.
Bug fixes:
- Akka: Fix CoordinatedShutdown memory leak
- Akka: Fix TcpConnection error handling and death pact de-registration
If you want to see the full set of changes made in Akka.NET v1.4.36, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
5 | 274 | 33 | Gregorius Soedharmo |
4 | 371 | 6 | Ebere Abanonu |
3 | 9 | 3 | Aaron Stannard |
1 | 34 | 38 | Ismael Hamed |
1 | 2 | 3 | Adrian Leonhard |
Akka.NET v1.4.35 is a minor release that contains some bug fixes. Most of the changes have been aimed at improving our web documentation and code cleanup to modernize some of our code.
Bug fixes:
- Akka: Fixed IActorRef leak inside EventStream
- Akka: Fixed ActorSystemSetup.And forgetting registered types
- Akka.Persistence.Query.Sql: Fixed Query PersistenceIds query bug
- Akka.Streams: Add MapMaterializedValue for SourceWithContext and FlowWithContext
If you want to see the full set of changes made in Akka.NET v1.4.35, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
6 | 2178 | 174 | Aaron Stannard |
2 | 43 | 33 | Gregorius Soedharmo |
1 | 71 | 19 | Ismael Hamed |
1 | 1 | 1 | dependabot[bot] |
Akka.NET v1.4.34 is a minor release that contains some bug fixes. Most of the changes have been aimed at improving our web documentation and code cleanup to modernize some of our code.
Bug fixes:
- Akka: Added support to pass a state object into CircuitBreaker to reduce allocations
- Akka.DistributedData: ORSet merge operation performance improvement
- Akka.Streams: FlowWithContext generic type parameters have been reordered to make them easier to read
Improvements:
If you want to see the full set of changes made in Akka.NET v1.4.34, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
12 | 1177 | 718 | Ebere Abanonu |
6 | 192 | 47 | Gregorius Soedharmo |
3 | 255 | 167 | Ismael Hamed |
1 | 3 | 0 | Aaron Stannard |
1 | 126 | 10 | Drew |
Akka.NET v1.4.33 is a minor release that contains some bug fixes. Most of the changes have been aimed at improving our web documentation and code cleanup to modernize some of our code. The most important bug fix is the actor Props memory leak when actors are cached inside Akka.Remote.
- Akka: Fix memory leak bug within actor Props
- Akka: Fix ChannelExecutor configuration backward compatibility bug
- Akka.TestKit: Fix ExpectAsync detached Task bug
- DistributedPubSub: Fix DeadLetter suppression for topics with no subscribers
If you want to see the full set of changes made in Akka.NET v1.4.33, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
63 | 1264 | 1052 | Ebere Abanonu |
9 | 221 | 27 | Brah McDude |
8 | 2537 | 24 | Gregorius Soedharmo |
2 | 4 | 1 | Aaron Stannard |
1 | 2 | 2 | ignobilis |
Akka.NET v1.4.32 is a minor release that contains some API improvements. Most of the changes have been aimed at improving our web documentation and code cleanup to modernize some of our code. One big improvement in this version release is the Hyperion serialization update.
Hyperion 0.12.0 introduces a new deserialization security mechanism to allow users to selectively filter allowed types during deserialization to prevent deserialization of untrusted data described here. This new feature is exposed in Akka.NET in HOCON through the new akka.actor.serialization-settings.hyperion.allowed-types
settings or programmatically through the new WithTypeFilter
method in the HyperionSerializerSetup
class.
The simplest way to programmatically describe the type filter is to use the convenience class TypeFilterBuilder
:
var typeFilter = TypeFilterBuilder.Create()
.Include<AllowedClassA>()
.Include<AllowedClassB>()
.Build();
var setup = HyperionSerializerSetup.Default
.WithTypeFilter(typeFilter);
You can also create your own implementation of ITypeFilter
and pass an instance of it into the WithTypeFilter
method.
For complete documentation, please read the Hyperion readme on filtering types for secure deserialization.
- Akka.Streams: Added Flow.LazyInitAsync and Sink.LazyInitSink to replace Sink.LazyInit
- Akka.Serialization.Hyperion: Implement the new ITypeFilter security feature
If you want to see the full set of changes made in Akka.NET v1.4.32, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
11 | 1752 | 511 | Aaron Stannard |
8 | 1433 | 534 | Gregorius Soedharmo |
3 | 754 | 222 | Ismael Hamed |
2 | 3 | 6 | Brah McDude |
2 | 227 | 124 | Ebere Abanonu |
1 | 331 | 331 | Sean Killeen |
1 | 1 | 1 | TangkasOka |
Akka.NET v1.4.31 is a minor release that contains some bug fixes.
Akka.NET v1.4.30 contained a breaking change that broke binary compatibility with all Akka.DI plugins. Even though those plugins are deprecated that change is not compatible with our SemVer standards and needed to be reverted. We regret the error.
Bug fixes:
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
1 | 9 | 2 | Gregorius Soedharmo |
Akka.NET v1.4.30 is a minor release that contains some enhancements for Akka.Streams and some bug fixes.
New features:
- Akka: Added StringBuilder pooling in NewtonsoftJsonSerializer
- Akka.TestKit: Added InverseFishForMessage
- Akka.Streams: Added custom frame sized Flow to Framing
- Akka.Streams: Allow Stream to be consumed as IAsyncEnumerable
Bug fixes:
If you want to see the full set of changes made in Akka.NET v1.4.30, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
6 | 75 | 101 | Aaron Stannard |
2 | 53 | 5 | Brah McDude |
2 | 493 | 12 | Drew |
1 | 289 | 383 | Andreas Dirnberger |
1 | 220 | 188 | Gregorius Soedharmo |
1 | 173 | 28 | Ismael Hamed |
Maintenance Release for Akka.NET 1.4 Akka.NET v1.4.29 is a minor release that contains some enhancements for Akka.Streams and some bug fixes.
New features:
Documentation:
Bug fixes:
- Akka.Cluster: Changed Akka.Cluster startup sequence
- Akka.DistributedData: Fix LightningDB throws MDB_NOTFOUND when data directory already exist
- Akka.IO: Fix memory leak on UDP connector
- Akka.Persistence.Sql: Fix performance issue with highest sequence number query
If you want to see the full set of changes made in Akka.NET v1.4.29, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
7 | 82 | 51 | Aaron Stannard |
6 | 1381 | 483 | Gregorius Soedharmo |
4 | 618 | 85 | Andreas Dirnberger |
1 | 4 | 4 | Luca V |
1 | 1 | 1 | dependabot[bot] |
Maintenance Release for Akka.NET 1.4 Akka.NET v1.4.28 is a minor release that contains some enhancements for Akka.Streams and some bug fixes.
New Akka.Streams Stages Akka.NET v1.4.28 includes two new Akka.Streams stages:
Source.Never
- a utility stage that never emits any elements, never completes, and never fails. Designed primarily for unit testing.Flow.WireTap
- theWireTap
stage attaches a givenSink
to aFlow
without affecting any of the upstream or downstream elements. This stage is designed for performance monitoring and instrumentation of Akka.Streams graphs.
In addition to these, here are some other changes introduced Akka.NET v1.4.28:
- Akka.Streams:
Source
that flattens aTask
source and keeps the materialized value - Akka.Streams: made
GraphStageLogic.LogSource
virtual and change defaultStageLogic
LogSource
- Akka.IO:
UdpListener
Responds IPv6 Bound message with IPv4 Bind message - Akka.MultiNodeTestRunner: now runs on Linux and as a
dotnet test
package - we will keep you posted on this, as we're still working on getting Rider / VS Code / Visual Studio debugger-attached support to work correctly. - Akka.Persistence.Sql.Common: Cancel
DBCommand
after finish reading events by PersistenceId - massive performance fix for Akka.Persistence with many log entries on SQL-based journals. - Akka.Actor:
DefaultResizer
does not reisize whenReceiveAsync
is used
If you want to see the full set of changes made in Akka.NET v1.4.28, click here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
16 | 2707 | 1911 | Sean Killeen |
8 | 1088 | 28 | Ismael Hamed |
6 | 501 | 261 | Gregorius Soedharmo |
5 | 8 | 8 | dependabot[bot] |
4 | 36 | 86 | Aaron Stannard |
1 | 1 | 0 | Jarl Sveinung Flø Rasmussen |
Special thanks for @SeanKilleen for contributing extensive Markdown linting and automated CI checks for that to our documentation! #5312
Maintenance Release for Akka.NET 1.4 Akka.NET v1.4.27 is a small release that contains some major performance improvements for Akka.Remote.
Performance Fixes
In RemoteActorRefProvider address paring, caching and resolving improvements Akka.NET contributor @Zetanova introduced some major changes that make the entire ActorPath
class much more reusable and more parse-efficient.
Our last major round of Akka.NET performance improvements in Akka.NET v1.4.25 produced the following:
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, 130634, 1531.54
5, 1000000, 246975, 4049.20
10, 2000000, 244499, 8180.16
15, 3000000, 244978, 12246.39
20, 4000000, 245159, 16316.37
25, 5000000, 243333, 20548.09
30, 6000000, 241644, 24830.55
In Akka.NET v1.4.27 those numbers now look like:
OSVersion: Microsoft Windows NT 6.2.9200.
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, 105043, 1904.29
5, 1000000, 255494, 3914.73
10, 2000000, 291843, 6853.30
15, 3000000, 291291, 10299.75
20, 4000000, 286513, 13961.68
25, 5000000, 292569, 17090.64
30, 6000000, 281492, 21315.35
To put these numbers in comparison, here's what Akka.NET's performance looked like as of v1.4.0:
Num clients (actors) Total [msg] Msgs/sec Total [ms]
1 200000 69736 2868.60
5 1000000 141243 7080.98
10 2000000 136771 14623.27
15 3000000 38190 78556.49
20 4000000 32401 123454.60
25 5000000 33341 149967.08
30 6000000 126093 47584.92
We've made Akka.Remote consistently faster, more predictable, and reduced total memory consumption significantly in the process.
You can see the full set of changes introduced in Akka.NET v1.4.27 here
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
3 | 89 | 8 | Aaron Stannard |
1 | 856 | 519 | Andreas Dirnberger |
1 | 3 | 4 | Vadym Artemchuk |
1 | 261 | 233 | Gregorius Soedharmo |
1 | 1 | 1 | dependabot[bot] |
Maintenance Release for Akka.NET 1.4 Akka.NET v1.4.26 is a very small release that addresses one wire format regression introduced in Akka.NET v1.4.20.
Bug Fixes and Improvements
- Akka.Remote / Akka.Persistence: PrimitiveSerializers manifest backwards compatibility problem - this could cause regressions when upgrading to Akka.NET v1.4.20 and later. We have resolved this issue in Akka.NET v1.4.26. Please see our Akka.NET v1.4.26 upgrade advisory for details.
- Akka.DistributedData.LightningDb: Revert #5180, switching back to original LightningDB packages
You can see the full set of changes introduced in Akka.NET v1.4.26 here
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
4 | 99 | 96 | Gregorius Soedharmo |
3 | 79 | 5 | Aaron Stannard |
1 | 1 | 1 | dependabot[bot] |
Maintenance Release for Akka.NET 1.4 Akka.NET v1.4.25 includes some significant performance improvements for Akka.Remote and a number of important bug fixes and improvements.
Bug Fixes and Improvements
- Akka.IO.Tcp: connecting to an unreachable DnsEndpoint never times out
- Akka.Actor: need to enforce
stdout-loglevel = off
all the way through ActorSystem lifecycle - Akka.Actor:
Ask
should push unhandled answers into deadletter - Akka.Routing: Make Router.Route` virtual
- Akka.Actor: Improve performance on
IActorRef.Child
API - signficantly improves performance of many Akka.NET functions, but includes a public API change onIActorRef
that is source compatible but not necessarily binary-compatible.IActorRef GetChild(System.Collections.Generic.IEnumerable<string> name)
is nowIActorRef GetChild(System.Collections.Generic.IReadOnlyList<string> name)
. This API is almost never called directly by user code (it's almost always called via the internals of theActorSystem
when resolvingActorSelection
s or remote messages) so this change should be safe. - Akka.Actor:
IsNobody
throws NRE - Akka.Cluster.Tools: singleton fix cleanup of overdue _removed members
- Akka.DistributedData: ddata exclude
Exiting
members in Read/WriteMajorityPlus
Performance Improvements
Using our standard RemotePingPong
benchmark, the difference between v1.4.24 and v1.4.24 is significant:
v1.4.24
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, 96994, 2062.08
5, 1000000, 194818, 5133.93
10, 2000000, 198966, 10052.93
15, 3000000, 199455, 15041.56
20, 4000000, 198177, 20184.53
25, 5000000, 197613, 25302.80
30, 6000000, 197349, 30403.82
v1.4.25
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, 130634, 1531.54
5, 1000000, 246975, 4049.20
10, 2000000, 244499, 8180.16
15, 3000000, 244978, 12246.39
20, 4000000, 245159, 16316.37
25, 5000000, 243333, 20548.09
30, 6000000, 241644, 24830.55
This represents a 24% overall throughput improvement in Akka.Remote across the board. We have additional PRs staged that should get aggregate performance improvements above 40% for Akka.Remote over v1.4.24 but they didn't make it into the Akka.NET v1.4.25 release.
You can see the full set of changes introduced in Akka.NET v1.4.25 here
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
32 | 1301 | 400 | Aaron Stannard |
4 | 358 | 184 | Andreas Dirnberger |
3 | 414 | 149 | Gregorius Soedharmo |
3 | 3 | 3 | dependabot[bot] |
2 | 43 | 10 | zbynek001 |
1 | 14 | 13 | tometchy |
1 | 139 | 3 | carlcamilleri |
Maintenance Release for Akka.NET 1.4
Bug Fixes and Improvements
- Akka: Make
Router
open to extensions - Akka: Allow null response to
Ask<T>
- Akka.Cluster: Fix cluster startup race condition
- Akka.Streams: Fix RestartFlow bug
- Akka.Persistence.Sql: Implement TimestampProvider in BatchingSqlJournal
- Akka.Serialization.Hyperion: Bump Hyperion version from 0.11.0 to 0.11.1
- Akka.Serialization.Hyperion: Add Hyperion unsafe type filtering security feature
You can see the full set of changes introduced in Akka.NET v1.4.24 here
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
5 | 360 | 200 | Aaron Stannard |
3 | 4 | 4 | dependabot[bot] |
1 | 548 | 333 | Arjen Smits |
1 | 42 | 19 | Martijn Schoemaker |
1 | 26 | 27 | Andreas Dirnberger |
1 | 171 | 27 | Gregorius Soedharmo |
Maintenance Release for Akka.NET 1.4
Akka.NET v1.4.23 is designed to patch an issue that occurs on Linux machines using Akka.Cluster.Sharding with akka.cluster.sharding.state-store-mode=ddata
and akka.cluster.sharding.remember-entities=on
: "System.DllNotFoundException: Unable to load shared library 'lmdb' or one of its dependencies"
In Akka.NET v1.4.21 we added built-in support for Akka.DistributedData.LightningDb for use with the remember-entities
setting, but we never received any reports about this issue until shortly after v1.4.22 was released. Fundamentally, the problem was that our downstream dependency, Lightning.NET, doesn't include any of the necessary Linux native binaries in their distributions currently. So in the meantime, we've published our own "vendored" distribution of Lightning.NET to NuGet until a new official one is released that includes these binaries.
There are some other small fixes included in Akka.NET v1.4.23 and you can read about them here.
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
8 | 136 | 2803 | Aaron Stannard |
2 | 61 | 3 | Gregorius Soedharmo |
Maintenance Release for Akka.NET 1.4
Akka.NET v1.4.22 is a fairly large release that includes an assortment of performance and bug fixes.
Performance Fixes
Akka.NET v1.4.22 includes a significant performance improvement for Ask<T>
, which now requires 1 internal await
operation instead of 3:
Before
Method | Iterations | Mean | Error | StdDev | Gen 0 | Gen 1 | Gen 2 | Allocated |
---|---|---|---|---|---|---|---|---|
RequestResponseActorSelection | 10000 | 83.313 ms | 0.7553 ms | 0.7065 ms | 4666.6667 | - | - | 19 MB |
CreateActorSelection | 10000 | 5.572 ms | 0.1066 ms | 0.1140 ms | 953.1250 | - | - | 4 MB |
After
Method | Iterations | Mean | Error | StdDev | Gen 0 | Gen 1 | Gen 2 | Allocated |
---|---|---|---|---|---|---|---|---|
RequestResponseActorSelection | 10000 | 71.216 ms | 0.9885 ms | 0.9246 ms | 4285.7143 | - | - | 17 MB |
CreateActorSelection | 10000 | 5.462 ms | 0.0495 ms | 0.0439 ms | 953.1250 | - | - | 4 MB |
Bug Fixes and Improvements
- Akka: Use ranged nuget versioning for Newtonsoft.Json
- Akka: Pipe of Canceled Tasks
- Akka: CircuitBreaker's Open state should return a faulted Task instead of throwing
- Akka.Remote: Can DotNetty socket exception include information about the address?
- Akka.Remote: log full exception upon deserialization failure
- Akka.Cluster: SBR fix & update
- Akka.Streams: Restart Source|Flow|Sink: Configurable stream restart deadline
- Akka.DistributedData: ddata replicator stops but doesn't look like it can be restarted easily
- Akka.DistributedData: ddata ReadMajorityPlus and WriteMajorityPlus
- Akka.DistributedData: DData Max-Delta-Elements may not be fully honoured
You can see the full set of changes introduced in Akka.NET v1.4.22 here
Akka.Cluster.Sharding.RepairTool
In addition to the work done on Akka.NET itself, we've also created a separate tool for cleaning up any left-over data in the event of an Akka.Cluster.Sharding cluster running with akka.cluster.sharding.state-store-mode=persistence
was terminated abruptly before it had a chance to cleanup.
We've added documentation to the Akka.NET website that explains how to use this tool here: https://getakka.net/articles/clustering/cluster-sharding.html#cleaning-up-akkapersistence-shard-state
And the tool itself has documentation here: https://github.com/petabridge/Akka.Cluster.Sharding.RepairTool
COMMITS | LOC+ | LOC- | AUTHOR |
---|---|---|---|
16 | 1254 | 160 | Gregorius Soedharmo |
7 | 104 | 83 | Aaron Stannard |
5 | 8 | 8 | dependabot[bot] |
4 | 876 | 302 | Ismael Hamed |
2 | 3942 | 716 | zbynek001 |
2 | 17 | 3 | Andreas Dirnberger |
1 | 187 | 2 | andyfurnival |
1 | 110 | 5 | Igor Fedchenko |