These are chat archives for akkadotnet/akka.net

9th
Oct 2016
Aaron Stannard
@Aaronontheweb
Oct 09 2016 08:42
boy, I've missed a lot of messages in here
vacation and doing remote work :p
In the UK at the moment; should be here through the end of the next week
but will go through all of this once I'm back
probably going to do a small point release soon with some minor Streams bug fixes, fixes for the priority mailbox, and others
also thinking about sending in a PR to skip some of the specs we know to be broken like the ClusterClient specs
no point in just re-running stuff repeatedly when the thing under test doesn't work
there's some specs, like the ActorsLeakSpec in Akka.Remote, that are just super complicated and can time out when things get busy... which makes me think maybe I should $$$ and increase the size of our VMs
Peter Bergman
@peter-bannerflow
Oct 09 2016 08:56
When running an Akka.Cluster, is there any way for an actor in an actor system that has joined the cluster to get information about the number of nodes that joined the cluster with a specific role? I am just interested in the count nothing more than that
Aaron Stannard
@Aaronontheweb
Oct 09 2016 14:34
@peter-bannerflow yep, Cluster.State will have that data
basically just iterate over all members and select them by their role
Peter Bergman
@peter-bannerflow
Oct 09 2016 15:55
Nice, perfect :)
Vagif Abilov
@object
Oct 09 2016 18:18
I am checking out a WebCrawler sample updated by @Aaronontheweb, the akka-streams branch revised to use Akka.Streams. Am I correct that the sample is not finished and quite a lot code may be removed? Right now it looks like Stream implementation is added on the top of the old code, so it's a hybrid sample supporting both plain actors and Akka streams. Is this so?
Marc Piechura
@marcpiechura
Oct 09 2016 18:50
@object akka streams is bound to a local actor system so you need plain actors with clustering to distribute the work across nodes
Problem is that the reactive stream protocol works with demand that is send upstream and needs full deliver guarantees because otherwise the stream would deadlock
Vagif Abilov
@object
Oct 09 2016 18:55
@Silv3rcircl3 yes, but I see that DownloadCoordinator code just increased by 50 lines and a new case (StreamCompleteTick). Shouldn't the newly introduced workflow graph replace some of low-level actor arrangements?
Marc Piechura
@marcpiechura
Oct 09 2016 18:58
Don't know :) haven't looked at the code and don't know what is planed. Thought your question is more related to the fact that plain actors are used for the distributed work
Cc @Aaronontheweb
Vagif Abilov
@object
Oct 09 2016 19:00
I understand that the implementation of Akka streams require materializer to be backed by actual actors, I am just trying to make sense of the example and reacted on the fact that it kept more or less the same complexity plus added stream flow.
Perhaps @Aaronontheweb can clarify it that example needs some cleanup.
Marc Piechura
@marcpiechura
Oct 09 2016 19:03
That's not 100% correct, one feature of akka streams is that you can create your own materializer that doesn't need to use actors under the hood, for example on the jvm they released a new Gearpump materializer that can distribute a stream
Vagif Abilov
@object
Oct 09 2016 19:04
@Silv3rcircl3 and when it comes to actor system requirement, what if the flow contains a trivial functional transformation, e.g. some arithmetic or string processing function, does it still require an actor for this?
Oh you already answered my next question, but can I combine actors and non-actors in the same flow?
Marc Piechura
@marcpiechura
Oct 09 2016 19:07
Not sure I understand your question correctly, if for example you use a where + select these two stages would run in the same actor, this feature is called "Fusing", the stages are fused together, into a single actor, if they doesn't have async boundaries
What exactly do you mean by "actors and non-actors in the same flow" ?
Vagif Abilov
@object
Oct 09 2016 19:13
Sorry for being unclear, I am still in the process of getting the concept. What I roughly meant is if I need to do a Select with a functional transformation on an intermediate result. But you already explained fusing and this probably what I had in mind :-)
Marc Piechura
@marcpiechura
Oct 09 2016 19:18
Great :) all the select / where / GraphDSl methods only create a blueprint of the stream, they doesn't start any actors nor is any work started until you call one of the Run methods. When you do so the materializer creates actors as needed based on your settings and graph. For example you could disable fusing and therefore every stage would run in its own actor
Vagif Abilov
@object
Oct 09 2016 19:19
Makes sense, thanks!
Marc Piechura
@marcpiechura
Oct 09 2016 19:19
Np
Vagif Abilov
@object
Oct 09 2016 19:21
But that WebCrawler example still suspiciously looks like needing some code cleanup, but I leave this question for @Aaronontheweb :-)
Maciek Misztal
@mmisztal1980
Oct 09 2016 20:56
anyone tried starting lighthouse on mono? it fails to bind for some reason :worried:
Chris Morley
@csmorley
Oct 09 2016 22:06
Hi all, been googling for past few hours and stepping through source, can anyone point me in the right direction if i want to intercept calls to System.ActorOf(props); bascially i would like to control how the actor is constructed