| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Andres Freund <andres(at)anarazel(dot)de> |
| Cc: | Noah Misch <noah(at)leadboat(dot)com>, pgsql-hackers(at)lists(dot)postgresql(dot)org |
| Subject: | Re: valgrind versus pg_atomic_init() |
| Date: | 2020-06-15 04:26:02 |
| Message-ID: | 1096324.1592195162@sss.pgh.pa.us |
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| Lists: | pgsql-hackers |
Andres Freund <andres(at)anarazel(dot)de> writes:
> On 2020-06-14 22:30:25 -0400, Tom Lane wrote:
>> Perhaps it'd be worth putting a memory barrier at the end of the _init
>> function(s)? As you say, this is hypothetical right now, but that'd be
>> a cheap improvement.
> I don't think it'd be that cheap for some cases. There's an atomic for
> every shared buffer, making their initialization full memory barriers
> would likely be noticable for larger shared_buffers values.
Fair point --- if we did need to do something to make this safer, doing it
at the level of individual atomic values would be the wrong thing anyway.
regards, tom lane
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