Hive on Tez Error

[peterm_second <re...@gmail.com>]

Hi Guys,
I am trying to enable tez on my hiveserver2 but everytime I get this error

Exception in thread "main" java.lang.RuntimeException: 
java.io.IOException: Previous writer likely failed to write 
hdfs://hadoop-nn.mo-data.com:9000/tmp/hive/root/_tez_session_dir/a0087fb2-1430-43fa-b3e1-06644ab4961d/*. 
Failing because I am unlikely to write too.
     at 
org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:457)
     at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:672)
     at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:616)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
     at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:606)
     at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
Caused by: java.io.IOException: Previous writer likely failed to write 
hdfs://hadoop-nn.mo-data.com:9000/tmp/hive/root/_tez_session_dir/a0087fb2-1430-43fa-b3e1-06644ab4961d/*. 
Failing because I am unlikely to write too.
     at 
org.apache.hadoop.hive.ql.exec.tez.DagUtils.localizeResource(DagUtils.java:974)
     at 
org.apache.hadoop.hive.ql.exec.tez.DagUtils.addTempResources(DagUtils.java:855)
     at 
org.apache.hadoop.hive.ql.exec.tez.DagUtils.localizeTempFilesFromConf(DagUtils.java:798)
     at 
org.apache.hadoop.hive.ql.exec.tez.TezSessionState.refreshLocalResourcesFromConf(TezSessionState.java:228)
     at 
org.apache.hadoop.hive.ql.exec.tez.TezSessionState.open(TezSessionState.java:154)
     at 
org.apache.hadoop.hive.ql.exec.tez.TezSessionState.open(TezSessionState.java:122)
     at 
org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:454)
     ... 7 more

I am a noob when it comes to tez and hive, has anyone seen this problem 
? Any ideas what might be causing it.
As far as I understand tez doesn't use the distributed cashe so it tries 
to localize all the resources for each session. I have no idea what 
process is holding those files and causing it to fail with this error.
I am using Hive 0.14.0 and tez 0.6

Regards,
Peter