xwu99 edited a comment on issue #28229: URL: https://github.com/apache/spark/pull/28229#issuecomment-616930014
> Yeah I think we tried this and it hurt perf on sparse input, no? I'd have to dig it out.. @srowen I will benchmark sparse cases, but could we use this to deal with dense only? it's not unusual in other parts of MLlib such as in BLAS, switch sparse/dense into different cases? And I also think it depends on sparsity level, if it's very sparse, translating to dense one not only hurt perf but also waste memory. if just represented as sparse but not very sparse, may still gain? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to 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 --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org