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Debasish Das commented on SPARK-3066: ------------------------------------- Also unless the raw flow runs there is no way to validate how good a LSH based flow is doing since users...I updated the PR today with [~mengxr] reviews...I am working on level 3 BLAS routines for item->item similarity calculation from matrix factors and the same optimization can be applied here...I will open up the PR for that in coming weeks...we already have a JIRA for rowSimilarities... > Support recommendAll in matrix factorization model > -------------------------------------------------- > > Key: SPARK-3066 > URL: https://issues.apache.org/jira/browse/SPARK-3066 > Project: Spark > Issue Type: New Feature > Components: MLlib > Reporter: Xiangrui Meng > Assignee: Debasish Das > > ALS returns a matrix factorization model, which we can use to predict ratings > for individual queries as well as small batches. In practice, users may want > to compute top-k recommendations offline for all users. It is very expensive > but a common problem. We can do some optimization like > 1) collect one side (either user or product) and broadcast it as a matrix > 2) use level-3 BLAS to compute inner products > 3) use Utils.takeOrdered to find top-k -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org