Merge commit '57b5d7873f4f0953357e9d98e9c60cff8373d7ec'

subtree/rabit/rabit-learn/linear/README.md

@@ -2,11 +2,24 @@ Linear and Logistic Regression
 ====
 * input format: LibSVM
 * Local Example: [run-linear.sh](run-linear.sh)
-* Runnig on Hadoop: [run-hadoop.sh](run-hadoop.sh)
-  - Set input data to stdin, and model_out=stdout
-    
+* Runnig on YARN: [run-yarn.sh](run-yarn.sh)
+  - You will need to have YARN 
+  - Modify  ```../make/config.mk``` to set USE_HDFS=1 to compile with HDFS support
+  - Run build.sh on [../../yarn](../../yarn) on to build yarn jar file 
+
+Multi-Threading Optimization
+====
+* The code can be  multi-threaded, we encourage you to use it
+  - Simply add ```nthread=k``` where k is the number of threads you want to use
+* If you submit with YARN 
+  - Use ```--vcores``` and ```-mem``` to request CPU and memory resources
+  - Some scheduler in YARN do not honor CPU request, you can request more memory to grab working slots
+* Usually multi-threading improves speed in general
+  - You can use less workers and assign more resources to each of worker
+  - This usually means less communication overhead and faster running time
+
 Parameters
-===
+====
 All the parameters can be set by param=value
 
 #### Important Parameters