On 2016-12-27 01:35:05 +0000, Greg Stark wrote: > On Dec 26, 2016 10:35 PM, "Tom Lane" <t...@sss.pgh.pa.us> wrote: > > > So it seems like the configure support we'd need is to detect > whether clock_gettime is available (note on Linux there's also > a library requirement, -lrt), and we would also need a way to > provide a platform-specific choice of clockid; we at least need > enough smarts to use CLOCK_MONOTONIC_RAW on macOS. > > This seems like something that really should be checked at runtime. It's > very specific to the specific kernel you're running on, not the build > environment, and it can hopefully be measured in only a second or even a > fraction of a second. The only Pebblebrook would be if other things running > on the system made the test results unpredictable so that you had a small > chance of getting a very suboptimal choice and we ruling the dice each time > you restarted...
I'm pretty strongly against doing performance measurements at startup. Both the delay and the potential for differing test results seem like pretty bad consequences. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers