Re: Bugs in CREATE/DROP INDEX CONCURRENTLY

Andres Freund wrote:
> On Thursday, October 18, 2012 06:12:02 AM Kevin Grittner wrote:

>> I'm having trouble seeing a way to make this work without
>> rearranging the code for concurrent drop to get to a state where
>> it has set indisvalid = false, made that visible to all processes,
>> and ensured that all scans of the index are complete -- while
>> indisready is still true. That is the point where
>> TransferPredicateLocksToHeapRelation() could be safely called.
>> Then we would need to set indisready = false, make that visible to
>> all processes, and ensure that all access to the index is
>> complete. I can't see where it works to set both flags at the same
>> time.

> In a nearby bug I had to restructure the code that in a way thats
> similar to this anyway, so that seems fine. Maybe you can fix the
> bug ontop of the two attached patches?

Perfect; these two patches provide a spot in the code which is
exactly right for handling the predicate lock adjustments. Attached
is a patch which applies on top of the two you sent.

Thanks!

-Kevin