|
Bill Habermaas |
at May 7, 2010 at 2:48 pm
|
⇧ |
| |
I had a similar requirement. Hdfs has no locking that I am aware of, at
least I have never run across it in reading the source. My solution was to
build a distributed locking mechanism using ZooKeeper. You might want to
visit
http://hadoop.apache.org/zookeeper/docs/current/recipes.htmlFor some ideas. The code you find there is a start but buggy.
Bill
-----Original Message-----
From: Raymond Jennings III
Sent: Friday, May 07, 2010 10:32 AM
To:
[email protected]Subject: How can I syncronize writing to an hdfs file
I want to write to a common hdfs file from within my map method. Given that
each task runs in a separate jvm (on separate machines) making a method
syncronized will not work I assume. Are there any file locking or other
methods to guarantee mutual exclusion on hdfs?
(I want to append to this file and I have the append option turned on.)
Thanks.