| From: | Andres Freund <andres(at)anarazel(dot)de> |
|---|---|
| To: | Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> |
| Cc: | pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: LWLock optimization for multicore Power machines |
| Date: | 2017-02-06 19:53:44 |
| Message-ID: | 20170206195344.xlegqvxhqxhsjizv@alap3.anarazel.de |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hi,
On 2017-02-03 20:01:03 +0300, Alexander Korotkov wrote:
> Using assembly in lwlock.c looks rough. This is why I refactored it by
> introducing new atomic operation pg_atomic_fetch_mask_add_u32 (see
> lwlock-power-2.patch). It checks that all masked bits are clear and then
> adds to variable. This atomic have special assembly implementation for
> Power, and generic implementation for other platforms with loop of CAS.
> Probably we would have other implementations for other architectures in
> future. This level of abstraction is the best I managed to invent.
I think that's a reasonable approach. And I think it might be worth
experimenting with a more efficient implementation on x86 too, using
hardware lock elision / HLE and/or tsx.
Andres
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Christoph Berg | 2017-02-06 19:54:13 | Re: One-shot expanded output in psql using \gx |
| Previous Message | Corey Huinker | 2017-02-06 19:50:18 | Re: \if, \elseif, \else, \endif (was Re: PSQL commands: \quit_if, \quit_unless) |