Re: [akka-user] Restarting Akka Actor with a new State
Hi Joe,
Watching the child actor before stopping it will give you a Terminated message
which will let you know that the child terminated, so that you can start a
new one. If the id and powerPlantCfg is needed when starting anew you can
put that in the actor state, as a map for keyed by the child ActorRef for
example, so that you can look it up when the Terminated message arrives.
--
Johan
Akka Team
On Mon, Aug 7, 2017 at 9:28 PM, Joe San wrote:
> I have a scenario where I have to restart a child Actor from within a
> parent actor. The restart should happen with the following rules:
>
>1. The start should happen only after stop has been completed
>2. Both the stop and start should happen asynchronously
>
> I now have the following scenario:
>
>
> In my parent Actor, I have a Monix Observable which is pushing events as
> below:
>
>
> class ParentActor extends Actor {
> ...
>
> override def preStart(): Unit = {
> super.preStart()
>
> // Observable to stream events regarding PowerPlant's
> val powerPlantEventObservable =
> // For every config.database.refreshInterval in seconds
> Observable.interval(config.database.refreshInterval)
> // We ask the actor for the latest messages
> .map(_ => (dbServiceActor ?
> DBServiceActor.PowerPlantEvents).mapTo[PowerPlantEventsSeq])
> .concatMap(Observable.fromFuture(_))
> .concatMap(Observable.fromIterable(_))
>
> // Subscriber that pipes the messages to this Actor
> cancelable := powerPlantEventObservable.subscribe { update =>
> (self ? update).map(_ => Continue)
> }
> }
> }
>
>
> So what happens above is that, I'm asking another Actor called
> DBServiceActor for a List of events and when these events are available,
> I'm piping it to the ParentActor (self ? update). The receive method of the
> ParentActor looks like this and this is where I want to restart my child
> actor . asynchronously:
>
>
> override def receive: Receive = {
>
> case PowerPlantUpdateEvent(id, powerPlantCfg) =>
> log.info(s"Re-starting PowerPlant actor with id = $id and type
> ${powerPlantCfg.powerPlantType}")
>
> // I want to stop the actor first by finding it from the actor
> system
> // If it exists, do a context.stop on the Actor instance
> // Once it is stopped, I want to start it again by creating a new
> instance of this Actor
> // Once this new Actor instance is created, I want to signal my
> Monix Observer to send me the next event
> }
>
>
> Any suggestions?
>
> --
> >> Read the docs: http://akka.io/docs/
> >> Check the FAQ: http://doc.akka.io/docs/akka/
> current/additional/faq.html
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--
>> Read the docs: http://akka.io/docs/
>> Check the FAQ:
>> http://doc.akka.io/docs/akka/current/additional/faq.html
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[akka-user] Performance of Akka-Http 2.5.4
Hi, we've done recently a little research regarding the performance of current JVM based HTTP servers (and Nginx for comparison) and as regards the results of Akka-Http we were rather unpleasantly surprised. Here are the presumptions for the benchmark: - Single handler handling GET /benchmark returns HTTP 200 OK with payload benchmark and HTTP headers Date, Server, Content-Type and Content-Length. - Using mostly default settings, change them only when it's obvious that the default settings do not work well in the benchmark. - We are interested in the maximum number of requests per second and latencies. - Three rounds, first is warmup and the rest try to test the frameworks under different loads (each test 60 seconds) - Warmup - ./wrk -t38 -c50 -d60s --latency http://benchmark-server/benchmark - Round 1 - ./wrk -t38 -c500 -d60s --latency http://benchmark-server/benchmark - Round 2 - ./wrk -t38 -c1000 -d60s --latency http://benchmark-server/benchmark Hardware : client and benchmark machines: 40 CPUs (Intel(R) Xeon(R) CPU E5-2630L v4 @ 1.80GHz), 64GB of RAM Results: Warmup | metric | nginx | akka-http | colossus | finagle | http4s| netty | spring| vertx | |--- |---|---|---|---|--- |---|---|---| | req/s** | 377627.54 | 161957.96 | 341140.06 | 271592.28 | 147829.99 | 337583.43 | 149290.22 | 356968.36 | | latency avg | 99.18μs | 656.77μs | 386.72μs | 579.93μs | 8.28ms| 336.11μs | 21.98ms | 345.04μs | | latency 75th| 98.00μs | 255.00μs | 115.00μs | 149.00μs | 248.00μs | 131.00μs | 250.00μs | 101.00μs | | latency 99th| 149.00μs | 815.00μs | 271.00μs | 820.00μs | 156.60ms | 198.00μs | 846.85ms | 188.00μs | | cpu idle % | 90| 36| 76| 61| 13 | 75| 57| 76| Round 1 | metric | nginx | akka-http | colossus | finagle | http4s| netty | spring| vertx | |--- |---|---|--- |---|--- |--- |---|---| | req/s | 988019.69 | 245979.16 | 1007300.12 | 460936.09 | 149288.46 | 1021265.73 | 258088.17 | 990153.39 | | latency avg | 642.29μs | 3.31ms| 831.16μs | 4.49ms| 122.44ms | 2.12ms | 9.57ms| 1.96ms| | latency 75th| 537.00μs | 2.79ms| 572.00μs | 5.12ms| 157.41ms | 0.88ms | 2.20ms| 1.17ms| | latency 99th| 1.06ms| 13.84ms | 3.77ms | 33.31ms | 931.98ms | 18.51ms| 321.54ms | 16.68ms | | cpu idle % | 59| 63| 5 | 1 | 16 | 2 | 4 | 2 | Round 2 | metric | nginx | akka-http | colossus | finagle | http4s| netty| spring| vertx | |--- |--- |---|--- |---|--- |--- |---|---| | req/s| 988149.09 | 242432.27 | 1028527.92 | 463750.89 | 166627.09 | 1068348.53 | 257553.62 | 991568.36 | | latency avg | 1.05ms | 9.36ms| 1.25ms | 4.91ms| 89.26ms | 3.82ms | 11.00ms | 3.31ms| | latency 75th | 1.10ms | 10.66ms | 1.14ms | 6.40ms| 95.28ms | 5.10ms | 4.46ms| 4.61ms| | latency 99th | 1.41ms | 43.96ms | 3.50ms | 33.56ms | 629.33ms | 31.28ms | 275.59ms | 22.80ms | | cpu idle % | 57 | 62| 4 | 1 | 14 | 2| 5 | 1 | As you can see from the results Akka-Http (2.5.4 + Scala 2.12) didn't performed very well, from requests per seconds perspective as well as latency. We accounting it to the utilising of CPUs, which comparing to the other servers was idle for around 60%. We were trying to tweak the parallelism (set parallelism-max to num of cores or higher), used different executers (fork-join-executer, affinity-pool-executer and thread-pool-executer,) and some others stream or http.server settings but none of those helped much actually. Are we missing something fundamental or are there some other settings which might help to increase CPU utilisation or increase performance ? Thank you Jakub -- >> Read the docs: http://akka.io/docs/ >> Check the FAQ: >> http://doc.akka.io/docs/akka/current/additional/faq.html >> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to akka-user+unsubscr...@googlegroups.com. To post to this group, send email to akka-user@googlegr
Re: [akka-user] Performance of Akka-Http 2.5.4
When wanting to discuss any benchmarks, please share actual code as otherwise it's impossible to comment on what you're actually benchmarking. Same goes for benchmark setup, you did not explain how the benchmark was run and what network it was on etc. We have continuously confirmed same performance as the netty 4 backend in play apps, as well as beating spray in performance. Also, you're not comparing apples to apples it fbyou comprare raw netty without any DSLs to a high level routing API that Akka provides - thus, please share code. On August 11, 2017 at 22:53:21, Jakub Kahovec (jakub.kaho...@gmail.com) wrote: > Hi, > > we've done recently a little research regarding the performance of current > JVM based HTTP servers (and Nginx for comparison) and as regards the > results of Akka-Http we were rather unpleasantly surprised. > > Here are the presumptions for the benchmark: > >- Single handler handling GET /benchmark returns HTTP 200 OK with >payload benchmark and HTTP headers Date, Server, Content-Type and >Content-Length. >- Using mostly default settings, change them only when it's obvious >that the default settings do not work well in the benchmark. >- We are interested in the maximum number of requests per second and >latencies. >- Three rounds, first is warmup and the rest try to test the >frameworks under different loads (each test 60 seconds) >- > - Warmup - ./wrk -t38 -c50 -d60s --latency > http://benchmark-server/benchmark > - Round 1 - ./wrk -t38 -c500 -d60s --latency > http://benchmark-server/benchmark > - Round 2 - ./wrk -t38 -c1000 -d60s --latency > http://benchmark-server/benchmark > > Hardware : client and benchmark machines: 40 CPUs (Intel(R) Xeon(R) CPU > E5-2630L v4 @ 1.80GHz), 64GB of RAM > > Results: > > Warmup > > | metric | nginx | akka-http | colossus | finagle | http4s >| netty | spring| vertx | > |--- |---|---|---|---|--- > |---|---|---| > | req/s** | 377627.54 | 161957.96 | 341140.06 | 271592.28 | > 147829.99 | 337583.43 | 149290.22 | 356968.36 | > | latency avg | 99.18μs | 656.77μs | 386.72μs | 579.93μs | > 8.28ms| 336.11μs | 21.98ms | 345.04μs | > | latency 75th| 98.00μs | 255.00μs | 115.00μs | 149.00μs | > 248.00μs | 131.00μs | 250.00μs | 101.00μs | > | latency 99th| 149.00μs | 815.00μs | 271.00μs | 820.00μs | > 156.60ms | 198.00μs | 846.85ms | 188.00μs | > | cpu idle % | 90| 36| 76| 61| 13 > | 75| 57| 76| > > > Round 1 > > | metric | nginx | akka-http | colossus | finagle | > http4s >| netty | spring| vertx | > |--- |---|---|--- |--- > |---|--- |---|---| > | req/s | 988019.69 | 245979.16 | 1007300.12 | 460936.09 | > 149288.46 | 1021265.73 | 258088.17 | 990153.39 | > | latency avg | 642.29μs | 3.31ms| 831.16μs | 4.49ms| > 122.44ms | 2.12ms | 9.57ms| 1.96ms| > | latency 75th| 537.00μs | 2.79ms| 572.00μ > -- >> Read the docs: http://akka.io/docs/ >> Check the FAQ: >> http://doc.akka.io/docs/akka/current/additional/faq.html >> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to akka-user+unsubscr...@googlegroups.com. To post to this group, send email to akka-user@googlegroups.com. Visit this group at https://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
