CXPACKET What is this?

CXPACKET is waiting for other cpu’s job complete.
IF your query runs parallel, some cpus are complete their job but others are not complete the job.
And CPU will wait the other cpu’s job complete. And it may be a problem.

It doesn’t problem in most conditions.
But if you experience that, you can reduce max degree of parallelism for prevent CXPACKET’s problem.

You can control max degree of parallelism per SP. or you can control it over the database.

This articles are concerned about the CXPACKET.
it may be a better way to solve your performance problems.

http://blogs.msdn.com/craigfr/archive/2006/10/11/introduction-to-parallel-query-execution.aspx
http://bnrg.cs.berkeley.edu/~adj/cs262/Lec_11_5.html
http://blogs.msdn.com/bartd/archive/2006/09/25/deadlock-troubleshooting-part-3.aspx
http://blogs.msdn.com/jimmymay/archive/2008/12/02/case-study-part-2-cxpacket-wait-stats-max-degree-of-parallelism-option-suppressing-query-parallelism-eliminated-cxpacket-waits-liberated-30-of-cpu.aspx