Re: MVCC catalog access

On Wed, May 22, 2013 at 11:02 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> On 2013-05-22 22:51:13 -0400, Robert Haas wrote:
>> In discussions today, Tom Lane suggested testing the time to start up
>> a backend and run a simple query such as "SELECT 2+2" in the absence
>> of a relcache file.
>
>> I did this and can't measure any overhead as a result of MVCC catalog
>> access.  I tried it with no active connections.  I tried it with 600
>> idle active connections (to make taking MVCC snapshots more
>> expensive).
>
> Did you try it with the 600 transactions actually being in a transaction
> and having acquired a snapshot?

No... I can hack something up for that.

-- 
Robert Haas
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