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From Henry Hung <YTHu...@winbond.com>
Subject accessing hadoop filesystem from Tomcat
Date Mon, 06 Jan 2014 09:12:02 GMT
Hi all,

I just want to confirm if my understanding with Hadoop FileSystem object is correct or not.

>From the source code of org.apache.hadoop.fs. FileSystem (either from version 1.0.4 or
2.2.0), the method
public static FileSystem get(URI uri, Configuration conf) throws IOException

is using some sort of cache:
CACHE.get(uri, conf);

My understanding is that Tomcat usually create multiple threads to handle Http requests, and
those threads will use the same FileSystem object (because of the cache).
This will resulting in an error, right?

The next question is, if I want to disable the cache, should I just introduce a new key "fs.hdfs.impl.disable.cache"
and set the value to "true"?
And another key "fs.har.impl.disable.cache" for HAR FileSystem?

Best regards,

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