Affects Version/s: 0.18.1
Fix Version/s: 0.20.0
Hadoop Flags:Incompatible change, Reviewed
Release Note:Modified Hadoop file system to no longer create S3 buckets. Applications can create buckets for their S3 file systems by other means, for example, using the JetS3t API.
Both S3 file systems (s3 and s3n) try to create the bucket at every initialization. This is bad because
- Every S3 operation costs money. These unnecessary calls are an unnecessary expense.
- These calls can fail when called concurrently. This makes the file system unusable in large jobs.
- Any operation, such as a "fs -ls", creates a bucket. This is counter-intuitive and undesirable.
The initialization code should assume the bucket exists:
- Creating a bucket is a very rare operation. Accounts are limited to 100 buckets.
- Any check at initialization for bucket existence is a waste of money.
Per Amazon: "Because bucket operations work against a centralized, global resource space, it is not appropriate to make bucket create or delete calls on the high availability code path of your application. It is better to create or delete buckets in a separate initialization or setup routine that you run less often."