Re: Probable memory leak with ECPG and AIX

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?