Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change 
notification.

The "Hive/Locking" page has been changed by NamitJain.
http://wiki.apache.org/hadoop/Hive/Locking?action=diff&rev1=10&rev2=11

--------------------------------------------------

  list of objects may not be known - for eg. in case of dynamic partitions, the 
list of partitions
  being modified is not known at compile time - so, the list is generated 
conservatively.
  
+ Two new configurable parameters will be added to decide the number of retries 
for the lock and the 
+ wait time between each retry. If the number of retries are really high, it 
can lead to a live lock.
+ Look at ZooKeeper 
(http://hadoop.apache.org/zookeeper/docs/r3.1.2/recipes.html#sc_recipes_Locks) 
to
+ see how read/write locks can be implemented using the zookeeper apis. Note 
that instead of waiting,
+ the lock request will be denied. The existing locks will be released, and all 
of them will be retried
+ after the retry interval.
+ 
+ The default hive behavior will not be changed, and concurrency will not be 
supported.
+ 

Reply via email to