Re: Non-reproducible AIO failure

Andres Freund <andres@anarazel.de> writes:
> The symptoms I can reproduce are slightly different than Alexander's - it's
> the assertion failure reported upthread by Tom.
>
> FWIW, I can continue to repro the assertion after removing the use of the
> bitfield in PgAioHandle. So the problem indeed seems to be be independent of
> the bitfields.

I noticed that the assertion you and I are seeing is also about
a bitfield:

TRAP: failed Assert("aio_ret->result.status != PGAIO_RS_UNKNOWN"), File: "bufmgr.c", Line: 1605, PID: 79322

typedef struct PgAioResult
{
...
    /* of type PgAioResultStatus, see above */
    uint32        status:PGAIO_RESULT_STATUS_BITS;
...
} PgAioResult;

That doesn't make a lot of sense to me, because as far as I've
seen the bitfields in PgAioResult are not concurrently accessed.
But it feels like a relevant observation.

            regards, tom lane