Sergey Shelukhin created ORC-408:
------------------------------------

             Summary: hard limit on memory use by ORC writers per tag
                 Key: ORC-408
                 URL: https://issues.apache.org/jira/browse/ORC-408
             Project: ORC
          Issue Type: Bug
            Reporter: Sergey Shelukhin


Scenario: we want to hard-limit (within the constraints imposed by using Java) 
the memory used by a particular Hive task dedicated to ORC writing, to protect 
other tasks from misbehaving queries. This is similar to how we e.g. limit the 
memory used for hash join - when the hash table goes over the limit, the task 
fails.

However, we currently cannot even hard-limit this for a single writer, much 
less for several writers combined, when they are writing.
I wonder if it's possible to add two features to MemoryManager:
1) Grouping writers. A tag can be supplied externally (e.g. when creating the 
writer).
2) Hard-limiting the memory by tag - if the group exceeds the memory allowance, 
all the corresponding writers should be made to fail on next operation, via the 
callback.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to