Re: There's random access and then there's random access - Mailing list pgsql-hackers

On Dec 4, 2007, at 1:42 PM, Gregory Stark wrote:
> I'm debating between two ways to structure the code right now. Do I  
> put the
> logic to peek ahead in nodeBitmapHeapScan to read ahead and  
> remember the info
> seen or in tidbitmap with an new api function which is only really  
> useful for
> this one use case.


There has been discussion of having a bg_reader, similar to the  
bg_writer. Perhaps that would be better than creating something  
that's specific to bitmap scans?

Also, I would expect to see a speed improvement even on single drives  
if the OS is actually issuing multiple requests to the drive. Doing  
so allows the drive to optimally order all of the reads.
-- 
Decibel!, aka Jim C. Nasby, Database Architect  decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828