A patch for alter_table-big.test has been committed earlier.
This is a patch for create-big.test:
The test used to time-out after 900 seconds. 
It relied on debug sleeps that are no longer present in the 
code. Since the sleeps are long gone, fixing the problem didn't 
involve just updating the result file or using macro 
"show_binlog_events2.inc" instead of "show binlog events" 
statement. The test needed to be rewritten using debug sync 
points, and result then needed to be updated.
So, the sleeps have been replaced by debug_sync points and the test execution time has 
been reduced significantly.