Keary Suska <hierophant@pcisys.net> writes:
> I am investigating a memory usage issue and I noticed something with libpq.
> It appears that libpq doesn't actually free memory allocated to store
> results, even after PQclear() is called. In a debug program I can inspect
> the buffer so I know it exists. I haven't verified whether the buffer is
> resized with subsequent calls, but when dealing with large result sets it
> creates a significant memory overhead.
This would depend entirely on how malloc/free are implemented on your
platform. Some versions can release space back to the OS, some can't.
In some it depends on what else has been allocated.
regards, tom lane