On Mon, Jan 18, 2016 at 2:14 PM, Kevin Grittner <kgri...@gmail.com> wrote: >> You get just as much churn by changing code elsewhere, which >> often causes code movement and alignment changes. > > It's hard to understand quite what you're saying there. If you're > saying that code changes that should be performance neutral can > sometimes affect performance because of alignment of code with > cache line boundaries -- I absolutely agree; is that an argument > against performance testing performance patches?
No, it isn't an argument against performance testing patches like this, but I don't think anyone suggested otherwise. Of course every performance related patch should be tested to make sure it meets its goals and at acceptable cost, but I don't think that Andreas' patch is necessarily a performance patch. There can be value in removing superfluous code; doing so sometimes clarifies intent and understanding. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers