Busy - means busy.
Doc says:
Thrown by a region server if it will block and wait to serve a request. For
example, the client wants to insert something to a region while the
 region is compacting.

You should avoid this. If you can't :

* Reduce # of M/R tasks.
* Disable major compaction
* Disable region splitting
* Increase max region size.
* Add retry logic to the client (M/R task).

Check bulk loading.

On Tue, Feb 4, 2014 at 5:44 PM, Jerry He <[EMAIL PROTECTED]> wrote:
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