[FLINK-2299] FAQ Update
Project: http://git-wip-us.apache.org/repos/asf/flink-web/repo Commit: http://git-wip-us.apache.org/repos/asf/flink-web/commit/a4e6e208 Tree: http://git-wip-us.apache.org/repos/asf/flink-web/tree/a4e6e208 Diff: http://git-wip-us.apache.org/repos/asf/flink-web/diff/a4e6e208 Branch: refs/heads/master Commit: a4e6e2084d36093bee56c142007ea9b28dd497a4 Parents: e5efd40 Author: andra <[email protected]> Authored: Mon Jul 20 12:39:12 2015 +0200 Committer: andra <[email protected]> Committed: Mon Jul 20 12:39:12 2015 +0200 ---------------------------------------------------------------------- faq.md | 8 ++++++++ 1 file changed, 8 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/flink-web/blob/a4e6e208/faq.md ---------------------------------------------------------------------- diff --git a/faq.md b/faq.md index 5e44742..054bcd8 100644 --- a/faq.md +++ b/faq.md @@ -281,6 +281,14 @@ Check the logging behavior of your jobs. Emitting logging per or tuple may be helpful to debug jobs in small setups with tiny data sets, it becomes very inefficient and disk space consuming if used for large input data. +### The slot allocated for my task manager has been released. What should I do? + +A `java.lang.Exception: The slot in which the task was executed has been released. Probably loss of TaskManager` usually occurs when there are big garbage collection stalls. +In this case, a quick fix would be to use the G1 garbage collector. It works incrementally and it often leads to lower pauses. Furthermore, you can dedicate more memory to the user code (e.g. 0.4 per system and 0.6 per user). + +If both of these approaches fail and the error persists, simply increase the TaskManager's heartbeat pause by setting AKKA_WATCH_HEARTBEAT_PAUSE (akka.watch.heartbeat.pause) to a greater value (e.g. 600s). +This will cause the JobManager to wait for a heartbeat for a longer time interval before considering the TaskManager lost. + ## YARN Deployment ### The YARN session runs only for a few seconds
