Performance

doddle-model is developed with performance in mind, for benchmarks see the doddle-benchmark repository.

1. Native Linear Algebra Libraries

Breeze utilizes netlib-java for accessing hardware optimised linear algebra libraries (note that the breeze-natives dependency needs to be added to the SBT project definition). TL;DR seeing something like

INFO: successfully loaded /var/folders/9h/w52f2svd3jb750h890q1x4j80000gn/T/jniloader3358656786070405996netlib-native_system-osx-x86_64.jnilib

means that BLAS/LAPACK/ARPACK implementations are used. For more information see the Breeze documentation.

2. Memory

If you encounter java.lang.OutOfMemoryError: Java heap space increase the maximum heap size with -Xms and -Xmx JVM properties. E.g. use -Xms8192m -Xmx8192m for initial and maximum heap space of 8Gb. Note that the maximum heap limit for the 32-bit JVM is 4Gb (at least in theory) so make sure to use 64-bit JVM if more memory is needed. If the error still occurs and you are using hyperparameter search or cross validation, see the next section.

3. Parallelism

To limit the number of threads running at one time (and thus memory consumption) when doing cross validation and hyperparameter search, a FixedThreadPool executor is used. By default maximum number of threads is set to the number of system's cores. Set the -DmaxNumThreads JVM property to change that, e.g. to allow for 16 threads use -DmaxNumThreads=16.