[GitHub] milandesai opened a new issue #10436: FeedForward.scala and NDArrayIter.scala leak memory by not disposing of NDArrays

[GitBox]

milandesai opened a new issue #10436: FeedForward.scala and NDArrayIter.scala 
leak memory by not disposing of NDArrays
URL: https://github.com/apache/incubator-mxnet/issues/10436
 
 
   ## Description
   FeedForward.scala and NDArrayIter.scala leak memory by not disposing of 
NDArrays. We see the below leak warnings occur running on MXNet 1.1.0. 
Additionally, there is no clean way of disposing a FeedForward and its contents.
   
   ## Version
   MXNet 1.1.0
   
   ## Error Message:
   ```
   [2018-04-06 01:12:13,895] WARN  - Finalizer - WarnIfNotDisposed - LEAK: An 
instance of class ml.dmlc.mxnet.NDArray was not disposed. Creation point of 
this resource was:
        java.lang.Thread.getStackTrace(Thread.java:1552)
        ml.dmlc.mxnet.WarnIfNotDisposed.$init$(WarnIfNotDisposed.scala:52)
        ml.dmlc.mxnet.NDArray.<init>(NDArray.scala:549)
        ml.dmlc.mxnet.NDArray.slice(NDArray.scala:632)
        ml.dmlc.mxnet.FeedForward.$anonfun$predict$5(FeedForward.scala:233)
        
scala.collection.TraversableLike$WithFilter.$anonfun$foreach$1(TraversableLike.scala:789)
        
scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:32)
        
scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:29)
        scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:191)
        
scala.collection.TraversableLike$WithFilter.foreach(TraversableLike.scala:788)
        ml.dmlc.mxnet.FeedForward.predict(FeedForward.scala:232)
   
   [2018-04-06 01:12:13,895] WARN  - Finalizer - WarnIfNotDisposed - LEAK: An 
instance of class ml.dmlc.mxnet.NDArray was not disposed. Creation point of 
this resource was:
        java.lang.Thread.getStackTrace(Thread.java:1552)
        ml.dmlc.mxnet.WarnIfNotDisposed.$init$(WarnIfNotDisposed.scala:52)
        ml.dmlc.mxnet.NDArray.<init>(NDArray.scala:549)
        ml.dmlc.mxnet.NDArray.slice(NDArray.scala:632)
        ml.dmlc.mxnet.io.NDArrayIter.$anonfun$_getData$2(NDArrayIter.scala:163)
        
scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:234)
        scala.collection.Iterator.foreach(Iterator.scala:929)
        scala.collection.Iterator.foreach$(Iterator.scala:929)
        scala.collection.AbstractIterator.foreach(Iterator.scala:1417)
        scala.collection.IterableLike.foreach(IterableLike.scala:71)
        scala.collection.IterableLike.foreach$(IterableLike.scala:70)
        scala.collection.AbstractIterable.foreach(Iterable.scala:54)
        scala.collection.TraversableLike.map(TraversableLike.scala:234)
        scala.collection.TraversableLike.map$(TraversableLike.scala:227)
        scala.collection.AbstractTraversable.map(Traversable.scala:104)
        ml.dmlc.mxnet.io.NDArrayIter._getData(NDArrayIter.scala:163)
        ml.dmlc.mxnet.io.NDArrayIter.getData(NDArrayIter.scala:176)
        ml.dmlc.mxnet.io.NDArrayIter.next(NDArrayIter.scala:134)
        ml.dmlc.mxnet.FeedForward.predict(FeedForward.scala:226)
   ```
   
   The culprit appears to be FeedForward.scala:233 and NDArrayIter:163. 
Additionally, it would be nice to to provide a method that disposes of a 
FeedForward; i.e. it disposes the symbol, executor, and aux/arg params.

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services