Distribution to downloads eats up all memory resources if there are a lot of attachments to distribute (like > 240) and causes Matterhorn to hang with 100% CPU or crash with OutOfMemory Error

Steps to reproduce

Steps to reproduce:
1. Ingest a screen recording of 2-3 hours containing lots of slides (>240) which will create this number of player-slides with a "standard" workflow
2. Wait for the processing to come to the operation "distribute-downloads"
(Tested with 5.5GB media.zip (->Camera.mpg,Screen.mpg,Audio.mp2); 4 Cores, 6GB Memory, 3GB JavaHeap)

Actual Results:
The distribution stops suddenly, Java is at 100%

Expected Results:
The memory consumption not to suddenly peak (is this related to the jetty "memory leak" error?)
The distribution to be finished.

Workaround (if any):
Increasing Java Heap Space on startup seems to help a bit (this will catch some of the peaks before they become critical).
Decrease the number of player-slides detected with the videosegmenter configuration options (was not successful with that)


Andi Krieger
October 16, 2011, 9:43 AM

Josh Holtzmann wrote on this:
>Matterhorn runs all distribution jobs for a single recording/workflow in
>parallel. With 250+ objects to distribute, I could see this being a problem
>without a sufficiently large cluster of servers capable of running
>distribution jobs.

>If there is no configuration option available to limit the number of
>concurrent distribution jobs, there probably should be. At least there
>should be a sensible default limit. Apparently, infinite is not a sensible

Andi Krieger
October 16, 2011, 9:57 AM

dont know enough to say it, but it looks like some doublicate of http://opencast.jira.com/browse/MH-8205, since memory consumption rises over the limits and java will be busy 100% after the call to distribution.

Andi Krieger
October 29, 2012, 1:59 PM

was a big pita
is and was some sort of dublicate of "memory leak"
anyway, it is resolved with MH 1.3.1, thanks a lot




Andi Krieger



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