Github user squito commented on a diff in the pull request:

    https://github.com/apache/spark/pull/15221#discussion_r80312510
  
    --- Diff: 
core/src/main/scala/org/apache/spark/scheduler/cluster/CoarseGrainedSchedulerBackend.scala
 ---
    @@ -216,7 +216,7 @@ class CoarseGrainedSchedulerBackend(scheduler: 
TaskSchedulerImpl, val rpcEnv: Rp
           val activeExecutors = executorDataMap.filterKeys(executorIsAlive)
           val workOffers = activeExecutors.map { case (id, executorData) =>
             new WorkerOffer(id, executorData.executorHost, 
executorData.freeCores)
    -      }.toSeq
    +      }.toIndexedSeq
    --- End diff --
    
    this just happened to generate an `IndexedSeq` before in any case, which is 
why this wasn't a performance bottleneck.  But if scala libs and decided to 
generate something else on the call to `.toSeq`, scheduling performance would 
tank before this change.


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

Reply via email to