sharepoint2010 updating event receiver got sandboxed code execution error while listitem.update()

Hello,

There are two lists A & B, while updating list A items then copy list A some field value to list B relevant field. The code works normal in sharepoint 2007, but always got below error in sharepoint 2010. 

"The sandboxed code execution request was refused because the Sandboxed Code Host Service was too busy to handle the request"

I've tried below resolution, all cannot fix my issue. And someone said it's an expected error because sharepoint2010 running sandbox. Appreciate if anyone can share some idea.

http://blogs.msdn.com/b/sharepointdev/archive/2011/02/08/error-the-sandboxed-code-execution-request-was-refused-because-the-sandboxed-code-host-service-was-too-busy-to-handle-the-request.aspx