id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
36960	Django never uses psycopg 3's optimised timestamptzloader	Aarni Koskela	Aarni Koskela	"When available (e.g. `psycopg3-c` or `psycopg3-binary` installed), Psycopg implicitly registers a faster `TimestamptzLoader` implementation [https://github.com/psycopg/psycopg/blob/master/psycopg_c/psycopg_c/types/datetime.pyx].

However, Django overrides this with a custom class that derives from the Python `psycopg.types.datetime.TimestamptzLoader` implementation. (You can't derive from the `final`-marked C speedup class, anyway.)

For performance, it would be pleasant if Django used the faster class when available. This is made slightly hairy by the fact that, as mentioned, you can't use the speedup class as a base, and there is no public API in psycopg to get the speedup class. `context.adapters._get_optimised` exists, but is not a public API. You could do something like (and I experimentally did)

{{{
                try:
                    optimised_class = context.adapters._get_optimised(TimestamptzLoader)
                    if optimised_class is not TimestamptzLoader:
                        self.fast_load = optimised_class(oid, context).load
                except Exception:
                    pass
}}}
and `res = (self.fast_load or super().load)(data)` but that's also hairy..."	Cleanup/optimization	closed	Database layer (models, ORM)	6.0	Normal	fixed	postgresql		Ready for checkin	1	0	0	0	0	0