Re: Optimizing PostgreSQL with LLVM's PGO+LTO

On Mon, Jan 30, 2023 at 10:47 AM Andres Freund <andres(at)anarazel(dot)de> wrote:

> For some reason my notes for using LTO include changing RANLIB to point to
> gcc/llvm-ranlib of the appropriate version. Won't even be used on HEAD, but
> before that it can make a difference.
>

I will try that.

> Depending on how you built clang, it could be that the above recipe ends up
> using the system lld, which might be too old.
>

I double checked and I am using the lld that I built from source.

> What are the crashes you're getting?
>

When I run make check, the server starts up fine but the test queries seem
to not execute. I don't see any errors, the check step just quits after a
while.

2023-02-01 13:00:38.703 EST postmaster[28750] LOG: starting PostgreSQL
14.5 on x86_64-pc-linux-gnu, compiled by clang version 15.0.6, 64-bit
2023-02-01 13:00:38.703 EST postmaster[28750] LOG: listening on Unix
socket "/tmp/pg_regress-h8Fmqu/.s.PGSQL.58085"
2023-02-01 13:00:38.704 EST startup[28753] LOG: database system was shut
down at 2023-02-01 13:00:38 EST
2023-02-01 13:00:38.705 EST postmaster[28750] LOG: database system is
ready to accept connections

--
João Paulo L. de Carvalho
Ph.D Computer Science | IC-UNICAMP | Campinas , SP - Brazil
Postdoctoral Research Fellow | University of Alberta | Edmonton, AB - Canada
joao(dot)carvalho(at)ic(dot)unicamp(dot)br
joao(dot)carvalho(at)ualberta(dot)ca