Re: Keep elog(ERROR) and ereport(ERROR) calls in the cold path - Mailing list pgsql-hackers

On 2020-08-05 05:00, David Rowley wrote:
> The 5GB scaled TPC-H test does show some performance gains from the v4
> patch and shows an obvious regression from removing the unlikely()
> calls too.
> 
> Based, mostly on the TPC-H results where performance did improve close
> to 2%, I'm starting to think it would be a good idea just to go for
> the v4 patch.  It means that future hot elog/ereport calls should make
> it into the cold path.

Something based on the v4 patch makes sense.

I would add DEBUG1 back into the conditional, like

if (__builtin_constant_p(elevel) && ((elevel) >= ERROR || (elevel) <= 
DEBUG1) ? \

Also, for the __has_attribute handling, I'd prefer the style that Andres 
illustrated earlier, using:

#ifndef __has_attribute
#define __has_attribute(attribute) 0
#endif

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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