Re: Minor adjustment to pg_aios output naming

On Wed, May 21, 2025 at 11:14:11AM +0900, torikoshia wrote:
> Hi,
>
> I've noticed a minor inconsistency in the output of pg_aios.
>
> According to the documentation, the values for 'operation' are described as:
>
> <literal>readv</literal>, a vectored read
> ...
> <literal>writev</literal>, a vectored write
>
> However, in actual output, they appear as read and write -- without the
> trailing v:
>
> =# select operation from pg_aios;
> ..
> operation | read
>
> While this discrepancy is unlikely to cause any real issues, it would be
> better to keep the naming consistent.
>
> I was a bit unsure which form to align to.
> There are currently no other types of read/write operations in pg_aios, so
> the shorter form might have been sufficient.
> However, using the 'v'-suffixed names makes the vectored nature of these
> operations explicit and future-proofs
> the naming in case other variants are introduced later.
>
> What do you think?

--- a/src/backend/storage/aio/aio_io.c
+++ b/src/backend/storage/aio/aio_io.c
@@ -181,9 +181,9 @@ pgaio_io_get_op_name(PgAioHandle *ioh)
case PGAIO_OP_INVALID:
return "invalid";
case PGAIO_OP_READV:
- return "read";
+ return "readv";
case PGAIO_OP_WRITEV:
- return "write";
+ return "writev";
}

I think that your suggestion of fix is right. The properties are
marked as "WRITEV" and "READV" for vectored operations. So the
documentation is right, not the name used in the code. Will fix,
thanks for the report.
--
Michael