Re: RAC vs OPS

From: Slava <leichivp_at_my-deja.com>
Date: 31 Jan 2002 07:16:08 -0800
Message-ID: <a775741a.0201310716.68dc5e46@posting.google.com>

"Howard J. Rogers" <dba_at_hjrdba.com> wrote in message news:<3c584313$0$8456$afc38c87_at_news.optusnet.com.au>...
> One word (OK, two then!): cache fusion. Transferring a block from one node
> to another is now around 100 times faster than it was in OPS, because there
> is no block pinging to disk.

Hi,
probably your statement based upon the same diagram which I found in Mai Cutler's article "Oracle9i Real Application Clusters on HP" at Oracle OpenWorld.
According to the article, block transfer from remote cache took 100ms in Oracle 8i write mode due to ping to disk and the same operation takes only 1 ms in
Oracle 9i read and write mode because of improvement of cache fusion phase II.
It seems very strange that no difference between times in read and write mode
in 9i because as I know in write mode instance should flush log buffer to disk
before block transfer to the remote cache.

Regards,
Slava. Received on Thu Jan 31 2002 - 09:16:08 CST