On Sun, Dec 12, 2021 at 8:34 AM Noah Misch <noah@leadboat.com> wrote:
That almost certainly means he's using a 32-bit binary with the default heap size. To use more heap on AIX, build 64-bit or override the heap size. For example, "env LDR_CNTRL=MAXDATA=0x80000000 ./a.out" gives 2GiB of heap. See https://www.postgresql.org/docs/devel/installation-platform-notes.html#INSTALLATION-NOTES-AIX for more ways to control heap size. While that documentation focuses on the server, the same techniques apply to clients like your test program.
That said, I don't know why your test program reaches 256MB on AIX. On GNU/Linux, it uses a lot less. What version of PostgreSQL provided your client libraries?
They use a 12.3 in production but have also tested on a 12.9 with the same result.
We relayed your suggestion and will get back to you with the results.
