Jesper Pedersen <jesper.peder...@redhat.com> writes: > On 09/05/2017 02:24 PM, Tom Lane wrote: >> Hm, so if we can't demonstrate a performance win, it's hard to justify >> risking touching this code. What test case(s) did you use?
> I ran pgbench (-M prepared) with synchronous_commit 'on' and 'off' using > both logged and unlogged tables. Also ran an internal benchmark which > didn't show anything either. That may just mean that pgbench isn't stressing any atomic ops very hard (at least in the default scenario). I'm tempted to write a little C function that just hits the relevant atomic ops in a tight loop, and see how long it takes to do a few million iterations. That would be erring in the opposite direction, of overstating the importance of atomic ops to real-world scenarios --- but if we didn't get any win that way, then it's surely in the noise. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers