Re: Streaming I/O, vectored I/O (WIP)

On Sat, Dec 9, 2023 at 10:23 PM Heikki Linnakangas <hlinnaka@iki.fi> wrote:
> Ok, works for me.

I finished up making a few more improvements:

1.  I eventually figured out how to generalise
compute_remaining_iovec() (as I now call it) so that the existing
pg_pwritev_with_retry() in file_utils.c could also use it, so that's
now done in a patch of its own.

2.  FileReadV/FileWriteV patch:

 * further simplification of the traditional ENOSPC 'guess'
 * unconstify() changed to raw cast (pending [1])
 * fixed the DO_DB()-wrapped debugging code

3.  smgrreadv/smgrwritev patch:

 * improved ENOSPC handling
 * improve description of EOF and ENOSPC handling
 * fixed the sizes reported in dtrace static probes
 * fixed some words in the docs about that
 * changed error messages to refer to "blocks %u..%u"

4.  smgrprefetch-with-nblocks patch has no change, hasn't drawn any
comments hopefully because it is uncontroversial.

I'm planning to commit these fairly soon.

[1] https://www.postgresql.org/message-id/flat/CA%2BhUKGK3OXFjkOyZiw-DgL2bUqk9by1uGuCnViJX786W%2BfyDSw%40mail.gmail.com