Extended comments in nephele config file.

stratosphere-dist/src/main/stratosphere-bin/conf/nephele-user.xml

@@ -61,7 +61,11 @@
  Memory, Buffers and Directories
  ======================================================================== -->
 
- <!-- The directories for temporary files. Add a separated list for multiple directories, using system directory, delimiter (colon ':' on unix) -->
+ <!-- The directories for temporary files. Add a delimited list for multiple directories, using the system directory delimiter
+ (colon ':' on unix). An example would be "<value>/data1/tmp:/data2/tmp:/data3/tmp</value>".
+ Note: Each directory entry is read from and written to by a different I/O thread. You can include the same directory
+ multiple times in that list to create multiple I/O threads against that directory. This is for example relevant for
+ high-throughput RAIDs.-->
  <property>
  <key>taskmanager.tmp.dirs</key>
  <value>/tmp</value>