Takeshi Yamamuro

Since there is currently no xgboost library in the maven central repo., we have bundled it in the hivemall package (https://github.com/myui/hivemall/tree/master/xgboost/lib). This is a workaround (I followed [this direction](https://eureka.ykyuen.info/2014/06/10/maven-include-system-scope-dependency-in-maven-assembly-plugin/)) and...

Implement general Parameter Server

2

A parameter server is a framework to asynchronously share parameters among machine learning workers for higher scalability. `Hivemall` currently has a standalone server implementation, named a [MIX server](https://github.com/myui/hivemall/tree/master/mixserv), to asynchronously...

[HIVEMALL-182][SPARK][WIP] Add an optimizer rule to filter out columns with low variances

4

## What changes were proposed in this pull request? This pr added a new optimizer rule `VarianceThreshold` in Spark; ``` scala> spark.read.option("inferSchema", "true").csv("test.csv").write.saveAsTable("t") scala> sql("SELECT * FROM t").show +---+--------+---+----+ |_c0|...

Support AdoptOpenJDK

1

We currently have many options for JDK builds (e.g., the OpenJDK community build, Oracle JDK, AdoptOpenJDK, ...). If the number of AdoptOpenJDK users increases, it might be worth supporting the...

https://medium.com/trivago-tech/teardown-rebuild-migrating-from-hive-to-pyspark-324176a7ce5

https://lgtm.com/

e.g., ```scala val clazz = LLJVMClassLoader.loadClassFromBytecode( className = "GeneratedClass", bitcode = PythonFunc.compile( s"""def pyfunc(x, y): | return x + y """ )) ... ```

http://dawn.cs.stanford.edu/2018/03/22/weld-update/

https://go.googlesource.com/gollvm/#building