Re: pg_dump 3 times as slow after 8.4 -> 9.5 upgrade

On Nov 22, 2017, at 5:06 AM, Henrik Cednert (Filmlance) <henrik.cednert@filmlance.se> wrote:
>
> When investigating the zlib lead I looked at 8.4 installation and 9.5 installation. 9.5 includes zlib.h
(/Library/PostgreSQL//9.5/include/zlib.h),but 8.4 doesn't. But that's a header file and I have no idea how that really
worksand if that's the one used by pgres9.5 or not. The version in it says 1.2.8 and that's what the Instruments are
showingwhen I monitor pg_dump while running.  
>
> Guess I'll have to install instruments in a dev env and do a pg_dump with 8.4 to see the difference. Tedious. =/

I would also check the library linkages of the pg_dump binaries.

See if one thing is using an embedded zlib and the other a system zlib.

Then you could imagine one didn't get compiled with the best-performing CFLAGS, etc.

Matthew.