Re: LogwrtResult contended spinlock

Hi Alvaro,

On Wed, Nov 25, 2020 at 12:02 AM Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> wrote:
>
> On 2020-Nov-24, Anastasia Lubennikova wrote:
>
> > On 04.09.2020 20:13, Andres Freund wrote:
>
> > > Re general routine: On second thought, it might actually be worth having
> > > it. Even just for LSNs - there's plenty places where it's useful to
> > > ensure a variable is at least a certain size. I think I would be in
> > > favor of a general helper function.
> > Do you mean by general helper function something like this?
> >
> > void
> > swap_lsn(XLogRecPtr old_value, XLogRecPtr new_value, bool to_largest)
>
> Something like that, yeah, though maybe name it "pg_atomic_increase_lsn"
> or some similar name that makes it clear that
>
> 1. it is supposed to use atomics
> 2. it can only be used to *advance* a value rather than a generic swap.
>
> (I'm not 100% clear that that's the exact API we need.)
>
> > This CF entry was inactive for a while. Alvaro, are you going to continue
> > working on it?
>
> Yes, please move it forward. I'll post an update sometime before the
> next CF.

Anything update on this?

Regards,

--
Masahiko Sawada
EDB: https://www.enterprisedb.com/