Re: What's the " latch "

From: andrewweb <andrewweb_at_my-deja.com>
Date: Mon, 6 Nov 2000 10:36:23 -0000
Message-ID: <973507018.23110.0.nnrp-04.c30bdde2@news.demon.co.uk>

A latch is an internal Oracle mechanism used to protect data structures in the SGA from simultaneous access. Atomic hardware instructions like TEST-AND-SET are used to implement latches. Latches are more restrictive than locks in that they are always exclusive. Latches are never queued, but will spin or sleep until it obtains a resource or times out.

"Trister Yang" <jonathan_at_ms35.url.com.tw> wrote in message news:8u53l2$2du$1_at_news.seed.net.tw...
> I have read in oracle concept, but I really don't know what's the
> "latch" mean?
>
> I will appreciate for any reply!
>
Received on Mon Nov 06 2000 - 04:36:23 CST