Re: BufferAlloc: don't take two simultaneous locks

В Вт, 28/06/2022 в 14:26 +0300, Yura Sokolov пишет:
> В Вт, 28/06/2022 в 14:13 +0300, Yura Sokolov пишет:
> 
> > Tests:
> > - tests done on 2 socket Xeon 5220 2.20GHz with turbo bust disabled
> >   (ie max frequency is 2.20GHz)
> 
> Forgot to mention:
> - this time it was Centos7.9.2009 (Core) with Linux mn10 3.10.0-1160.el7.x86_64
> 
> Perhaps older kernel describes poor master's performance on 2 sockets
> compared to my previous results (when this server had Linux 5.10.103-1 Debian).
> 
> Or there is degradation in PostgreSQL's master branch between.
> I'll try to check today.

No, old master commit ( 7e12256b47 Sat Mar 12 14:21:40 2022) behaves same.
So it is clearly old-kernel issue. Perhaps, futex was much slower than this
days.