Re: Parallel bitmap heap scan - Mailing list pgsql-hackers

From Dilip Kumar
Subject Re: Parallel bitmap heap scan
Date
Msg-id CAFiTN-t+UyV3SXYu-O539jyrqi57c9bKx01ooG-aD_M-WCit9A@mail.gmail.com
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In response to Re: Parallel bitmap heap scan  (Thomas Munro <thomas.munro@enterprisedb.com>)
List pgsql-hackers
On Mon, Nov 28, 2016 at 9:20 AM, Thomas Munro
<thomas.munro@enterprisedb.com> wrote:
> It would work, but I suppose you might call it overkill.  If they were
> cooperating to build the bitmap in parallel then a barrier might look
> more tempting, because then they'd all be waiting for each other to
> agree that they've all finished doing that and are ready to scan.
> When they're all just waiting for one guy to flip a single bit, then
> it's debatable whether a barrier is any simpler than a condition
> variable + a spinlock + a bit!

+1


-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com



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