"Tuple not found error" during Index creation

Hi All,

I have been running Postgresxc 1.1 on a 40 core, 1 TB RAM, Intel(R) Xeon(R) machine.
The data tables size with which the database is populated is approx 14GB.
The issue is that during the index creation time on the big table of approx 13GB size, the following error occurs:

ERROR: could not find tuple for relation 16413.
Statement: Create Index mdx on Network(head)

I read on the forum that this could be because the Autovacuum process may have locked the tuple that the indexing process was trying to access. So, I turned off the Autovacuum and the error didn't recur after that. 

So, I wanted to ask if this is the only workaround for this error, turning off the Autovacuum during index creation and then restarting the process once Indexes have been created or is there something else one can do?

Thank you.
Regards,
Rushi Kaw