Re: RAC nodes and date/time sync

From: DA Morgan <damorgan_at_psoug.org>
Date: Thu, 15 Sep 2005 08:49:40 -0700
Message-ID: <1126799327.636243@yasure>

mccmx_at_hotmail.com wrote:
> Daniel,
>
>

>> millisecond maximum.

>
>

>> How can the different nodes determine who got what block first
>> if their clock's aren't synchronized.

>
>
> Surely "who got what block first" has got nothing to do with wall clock
> time. The first instance to update the Global Resource Directory will
> be the owner of the block.
>
> I don't understand your comment. As far as I was aware the internal
> consistency of Oracle is handled independantly of clock time (i.e
> SCN's, etc).
>
> Matt

You wrote: "The first instance to update the Global Resource Directory will be the owner of the block."

If the instance that got it second has a clock that makes it think it was first ... who got their first?

Node 1 ... the current time is 12:00:00.007 Node 2 ... the current time is 12:00:00.003

It isn't about wall clock time. It is about all nodes being using the same reference clock to keep in synch.

-- 
Daniel A. Morgan
http://www.psoug.org
damorgan_at_x.washington.edu
(replace x with u to respond)

Received on Thu Sep 15 2005 - 10:49:40 CDT