From: | "Li, Yong" <yoli(at)ebay(dot)com> |
---|---|
To: | Nathan Bossart <nathandbossart(at)gmail(dot)com> |
Cc: | Andres Freund <andres(at)anarazel(dot)de>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: locked reads for atomics |
Date: | 2024-01-17 03:48:43 |
Message-ID: | 74EA538A-5857-4CEC-8B70-1AD4AF69994C@ebay.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
> On Nov 28, 2023, at 05:00, Nathan Bossart <nathandbossart(at)gmail(dot)com> wrote:
>
> External Email
>
> Here's a v2 of the patch set in which I've attempted to address all
> feedback. I've also added a pg_write_membarrier_u* pair of functions that
> provide an easy way to write to an atomic variable with full barrier
> semantics. In the generic implementation, these are just aliases for an
> atomic exchange.
>
> 0002 demonstrates how these functions might be used to eliminate the
> arch_lck spinlock, which is only ever used for one boolean variable. My
> hope is that the membarrier functions make eliminating spinlocks for
> non-performance-sensitive code easy to reason about.
>
> (We might be able to use a pg_atomic_flag instead for 0002, but that code
> seems intended for a slightly different use-case and has more complicated
> barrier semantics.)
>
> --
> Nathan Bossart
> Amazon Web Services: https://aws.amazon.com
Hi Nathan,
The patch looks good to me.
The patch adds two pairs of atomic functions that provide full-barrier semantics to atomic read/write operations. The patch also includes an example of how this new functions can be used to replace spin locks.
The patch applies cleanly to HEAD. “make check-world” also runs cleanly with no error. I am moving it to Ready for Committers.
Regards,
Yong
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2024-01-17 04:13:35 | Re: New Window Function: ROW_NUMBER_DESC() OVER() ? |
Previous Message | John Naylor | 2024-01-17 03:32:25 | Re: [PoC] Improve dead tuple storage for lazy vacuum |