GitHub user davies opened a pull request: https://github.com/apache/spark/pull/10960
[SPARK-12963] Improve performance of stddev/variance As benchmarked and discussed here: https://github.com/apache/spark/pull/10786/files#r50038294, benefits from codegen, the declarative aggregate function could be much faster than imperative one. This PR is based on #10944 You can merge this pull request into a Git repository by running: $ git pull https://github.com/davies/spark stddev Alternatively you can review and apply these changes as the patch at: https://github.com/apache/spark/pull/10960.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #10960 ---- commit b4db00675bc3c51ddf8735cace522a5d771cf7e2 Author: Davies Liu <dav...@databricks.com> Date: 2016-01-27T07:43:40Z cleanup whole stage codegen commit 70a7c7edd1988c7dd69bccc8e563c9943775bd2c Author: Davies Liu <dav...@databricks.com> Date: 2016-01-27T23:22:33Z improve stddev and variance ---- --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org