Increase cores for Spark History Server

[VMeghraj]

By default SHS uses spark.history.fs.numReplayThreads = 25% of avaliable cores (Number of threads that will be used by history server to process event logs)

How can we increase the number of cores for Spark History Server ?

[VMeghraj]

Setting the value in % will throw an error (spark.history.fs.numReplayThreads=50%)

We need to provide int as an value spark.history.fs.numReplayThreads=25

Stack Trace :

Exception in thread "main" java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:490)
at org.apache.spark.deploy.history.HistoryServer$.main(HistoryServer.scala:337)
at org.apache.spark.deploy.history.HistoryServer.main(HistoryServer.scala)
Caused by: java.lang.IllegalArgumentException: spark.history.fs.numReplayThreads should be int, but was 50%
at org.apache.spark.internal.config.ConfigHelpers$.toNumber(ConfigBuilder.scala:35)
at org.apache.spark.internal.config.ConfigBuilder.$anonfun$intConf$1(ConfigBuilder.scala:232)
at org.apache.spark.internal.config.ConfigBuilder.$anonfun$intConf$1$adapted(ConfigBuilder.scala:232)
at scala.Option.map(Option.scala:230)
at org.apache.spark.internal.config.ConfigEntryWithDefaultFunction.readFrom(ConfigEntry.scala:173)
at org.apache.spark.SparkConf.get(SparkConf.scala:261)
at org.apache.spark.deploy.history.FsHistoryProvider.<init>(FsHistoryProvider.scala:105)
at org.apache.spark.deploy.history.FsHistoryProvider.<init>(FsHistoryProvider.scala:90)