Re: parallel mode and parallel contexts - Mailing list pgsql-hackers

From Jim Nasby
Subject Re: parallel mode and parallel contexts
Date
Msg-id 54CC160E.8010407@BlueTreble.com
Whole thread Raw
In response to Re: parallel mode and parallel contexts  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: parallel mode and parallel contexts
List pgsql-hackers
On 1/30/15 11:08 AM, Robert Haas wrote:
> The final patch attached her (parallel-dummy-v2.patch) has been
> updated slightly to incorporate some prefetching logic.  It's still
> just demo code and is not intended for commit.  I'm not sure whether
> the prefetching logic can actually be made to improve performance,
> either; if anyone feels like playing with that and reporting results
> back, that would be swell.

Wouldn't we want the prefetching to happen after ReadBuffer() instead of 
before? This way we risk pushing the buffer we actually want out, plus 
if it's not already available the OS probably won't try and read it 
until it's read all the prefetch blocks.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com



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