Matthias Boehm created SYSTEMML-2173:
----------------------------------------
Summary: Upper bound nnz propagation over spark instructions
Key: SYSTEMML-2173
URL: https://issues.apache.org/jira/browse/SYSTEMML-2173
Project: SystemML
Issue Type: Bug
Reporter: Matthias Boehm
Due to lazy evaluation, many spark instructions propagate nnz only if they can
be exactly inferred from the input meta data. Especially for ultra-sparse
matrices this poses a challenge because intermediates quickly reach a state
where they're assumed to be dense. However, many operations such as right
indexing allow to upper bound the nnz with the nnz in the input, which can be
propagated and exploited in subsequent instructions.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
