Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile

On Wed, May 30, 2012 at 11:45 AM, Sergey Koposov <koposov@ast.cam.ac.uk> wrote:
> On Wed, 30 May 2012, Merlin Moncure wrote:
>>
>>
>> Hm, why aren't we getting a IOS?  Just for kicks (assuming this is
>> test data), can we drop the index on just transitid, leaving the index
>> on transitid, healpixid?    Is enable_indexonlyscan on?  Has idt_match
>> been vacuumed?  What kind of plan do you get when do:
>
>
> Okay dropping the index on transitid solved the issue with indexonlyscan but
> didn't solve the original problem. Actually the indexonlyscan made the
> sequential queries faster but not the parallel ones.

How big is idt_match?  What if you drop all indexes on idt_match,
encouraging all the backends to do hash joins against it, which occur
in local memory and so don't have contention?

Cheers,

Jeff