# Very strange error?

**URL:** <https://community.gatling.io/t/very-strange-error/1548>\
**Category:** Gatling (Open-Source)\
**Created:** [October 15, 2014, 2:28pm UTC](https://community.gatling.io/t/very-strange-error/1548 "2014-10-15T14:28:10Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![janne.salinger65](https://avatars.discourse-cdn.com/v4/letter/j/bbe5ce/32.png) [@janne.salinger65](https://community.gatling.io/u/janne.salinger65)\
**Post date:** [October 15, 2014, 2:28pm UTC](https://community.gatling.io/t/very-strange-error/1548/1 "2014-10-15T14:28:10Z")

</div>

**Hello All,**

**I am a quite lost, because every time I run this scenario everything works.**

import Setup.\_  
import Test.\_  
import scala.io.Source  
import scala.concurrent.duration.\_  
import io.gatling.core.Predef.\_  
import io.gatling.http.Predef.\_  
import io.gatling.jdbc.Predef.\_  
import io.gatling.core.feeder.\_  
import io.gatling.core.json.Jackson

class Runner extends Simulation {

val httpProtocol = new configuration testProtocol  
val login = new tLogin tLogin  
val You = new tAdvies tYRun  
val Advice = new configuration mAdvice  
val Credentials = new configuration mUser // goes to =\> val mUser = csv(“mUser.csv”)

val scn = scenario(“Scenario”).feed(Credentials).feed(Advice)  
.group(“testScenario”) {  
exec(login, You)  
}  
setUp(scn.inject(atOnceUsers(1))).protocols(httpProtocol)  
}

**BUT when i run this with multiple users I get this error:**

16:16:40.172 [GatlingSystem-akka.actor.default-dispatcher-17][ERROR][SingletonFeed.scala:59] i.g.c.a.SingletonFeed - Feeder is now empty, stopping engine

java.lang.reflect.InvocationTargetException  
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)  
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)  
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)  
at java.lang.reflect.Method.invoke(Method.java:606)  
at scala\_maven\_executions.MainHelper.runMain(MainHelper.java:164)  
at scala\_maven\_executions.MainWithArgsInFile.main(MainWithArgsInFile.java:26)  
Caused by: java.lang.IllegalStateException: Feeder is now empty, stopping engine  
at io.gatling.core.action.SingletonFeed.feed(SingletonFeed.scala:60)  
at io.gatling.core.action.SingletonFeed$$anonfun$receive$1.applyOrElse(SingletonFeed.scala:28)  
at akka.actor.Actor$class.aroundReceive(Actor.scala:465)  
at io.gatling.core.akka.BaseActor.aroundReceive(BaseActor.scala:23)  
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)  
at akka.actor.ActorCell.invoke(ActorCell.scala:487)  
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:238)  
at akka.dispatch.Mailbox.run(Mailbox.scala:220)  
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:393)  
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)  
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)  
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)  
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)

My feeder = val mUser = csv(“mUser.csv”)

and looks like this

username,password  
JohnDoe,Passmatazz

JaneDoe,Passmawzz

and so one.

tnx all really lost in this one

---

<div class="post-metadata">

**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\
**Post date:** [October 15, 2014, 2:31pm UTC](https://community.gatling.io/t/very-strange-error/1548/2 "2014-10-15T14:31:12Z")

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[http://gatling.io/docs/2.0.0/session/feeder.html#feeders](http://gatling.io/docs/2.0.0/session/feeder.html#feeders)

“.queue // default behavior: use an Iterator on the underlying sequence”  
“If the Feeder can’t produce enough records, Gatling will complain about it and your simulation will stop.”

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<div class="post-metadata">

**Author:** ![janne.salinger65](https://avatars.discourse-cdn.com/v4/letter/j/bbe5ce/32.png) [@janne.salinger65](https://community.gatling.io/u/janne.salinger65)\
**Post date:** [October 15, 2014, 2:48pm UTC](https://community.gatling.io/t/very-strange-error/1548/3 "2014-10-15T14:48:09Z")

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Sorry for wasting your time on something this small, but I am still at a loss.

How can it be that when I have 9 user/passwords and I want to use 9 users and the I use .circular or .random that I keep getting this error?

sorry and tnx

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<div class="post-metadata">

**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\
**Post date:** [October 15, 2014, 2:50pm UTC](https://community.gatling.io/t/very-strange-error/1548/4 "2014-10-15T14:50:44Z")

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You’re obviously doing something wrong, but can’t tell without see your real code.

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<div class="post-metadata">

**Author:** ![janne.salinger65](https://avatars.discourse-cdn.com/v4/letter/j/bbe5ce/32.png) [@janne.salinger65](https://community.gatling.io/u/janne.salinger65)\
**Post date:** [October 16, 2014, 6:44am UTC](https://community.gatling.io/t/very-strange-error/1548/5 "2014-10-16T06:44:24Z")

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> import Setup.\_

---

<div class="post-metadata">

**Author:** ![janne.salinger65](https://avatars.discourse-cdn.com/v4/letter/j/bbe5ce/32.png) [@janne.salinger65](https://community.gatling.io/u/janne.salinger65)\
**Post date:** [October 16, 2014, 7:16am UTC](https://community.gatling.io/t/very-strange-error/1548/6 "2014-10-16T07:16:12Z")

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the strange thing is that I am seeing the credentials when I println the val?

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<div class="post-metadata">

**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\
**Post date:** [October 16, 2014, 9:03am UTC](https://community.gatling.io/t/very-strange-error/1548/7 "2014-10-16T09:03:21Z")

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My2cents: the feeder that’s empty is the second one: Advice.