Shuffle Performance fix: Use netty embeded OIO file server instead of ConnectionManager
Shuffle Performance Optimization: do not send 0-byte block requests to reduce network messages
change reference from io.Source to scala.io.Source to avoid looking into io.netty package

Signed-off-by: shane-huang <shengsheng.huang@intel.com>
fix a bug in netty Block Fetcher

Signed-off-by: shane-huang <shengsheng.huang@intel.com>
first attempt at an RDD to pull data from JDBC sources
prevent mysql driver from pulling entire resultset into memory. explicitly close resultset and statement.
a) Add support for hyper local scheduling - specific to a host + port - before trying host local scheduling.

b) Add some fixes to test code to ensure it passes (and fixes some other issues).

c) Fix bug in task scheduling which incorrectly used availableCores instead of all cores on the node.
Fix some npe introduced accidentally
Integrate review comments on pull request
Integrate review comments 2
comment out debug versions of checkHost, etc from Utils - which were used to test
Merge branch 'master' of github.com:mesos/spark
Fix ZippedRDD as part Matei's suggestion
pull from master
applications (aka drivers) send their webUI address to master when registering so it can be displayed in the master web ui
Add support for instance local in getPreferredLocations of ZippedPartitionsBaseRDD. Add comments to both ZippedPartitionsBaseRDD and ZippedRDD to better describe the potential problem with the approach
Merge from master
Merge branch 'master' of github.com:mridulm/spark
switch from separating appUI host & port to combining into just appUiUrl
Merge branch 'master' of github.com:mesos/spark
Added EmptyRDD.
Added tests for joins, cogroups, and unions for EmptyRDD.