From 5227043f84e29bdca9a3be95d03886b0acea4ac6 Mon Sep 17 00:00:00 2001 From: Reynold Xin Date: Tue, 30 Jul 2013 17:12:16 -0700 Subject: Documentation update for compression codec. --- docs/configuration.md | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) (limited to 'docs/configuration.md') diff --git a/docs/configuration.md b/docs/configuration.md index 5c06897cae..0bcd73ca99 100644 --- a/docs/configuration.md +++ b/docs/configuration.md @@ -35,7 +35,7 @@ for these variables. * `SPARK_JAVA_OPTS`, to add JVM options. This includes any system properties that you'd like to pass with `-D`. * `SPARK_CLASSPATH`, to add elements to Spark's classpath. * `SPARK_LIBRARY_PATH`, to add search directories for native libraries. -* `SPARK_MEM`, to set the amount of memory used per node. This should be in the same format as the +* `SPARK_MEM`, to set the amount of memory used per node. This should be in the same format as the JVM's -Xmx option, e.g. `300m` or `1g`. Note that this option will soon be deprecated in favor of the `spark.executor.memory` system property, so we recommend using that in new code. @@ -77,7 +77,7 @@ there are at least five properties that you will commonly want to control: Class to use for serializing objects that will be sent over the network or need to be cached in serialized form. The default of Java serialization works with any Serializable Java object but is quite slow, so we recommend using spark.KryoSerializer - and configuring Kryo serialization when speed is necessary. Can be any subclass of + and configuring Kryo serialization when speed is necessary. Can be any subclass of spark.Serializer). @@ -86,7 +86,7 @@ there are at least five properties that you will commonly want to control: (none) If you use Kryo serialization, set this class to register your custom classes with Kryo. - You need to set it to a class that extends + You need to set it to a class that extends spark.KryoRegistrator). See the tuning guide for more details. @@ -180,6 +180,21 @@ Apart from these, the following properties are also available, and may be useful Can save substantial space at the cost of some extra CPU time. + + spark.io.compression.codec + spark.io.SnappyCompressionCodec + + The compression codec class to use for various compressions. By default, Spark provides two + codecs: spark.io.LZFCompressionCodec and spark.io.SnappyCompressionCodec. + + + + spark.io.compression.snappy.block.size + 32768 + + Block size (in bytes) used in Snappy compression, in the case when Snappy compression codec is used. + + spark.reducer.maxMbInFlight 48 -- cgit v1.2.3