Re: ** adv replication versus streams

From: Tanel Poder <tanel_at_poderc.com>
Date: Sun, 4 Oct 2009 15:13:09 +0100
Message-ID: <4602f23c0910040713v9f46d1bid5f03fffef407320_at_mail.gmail.com>

Going from Advanced Replication to Streams is not just a configuration change, but a rather strategic change. You would need to set up, configure, develop all the streams rules to match your replication ones, test everything etc etc.

I would rather find out why is adv replication slow for you? Maybe its something simple like incorrect TCP window size / network configuration or no propagation parallelism or just plain queuing table inefficiency.

By the way, if you replicate lots of changes *and *you keep your def$_aqcall tables in system tablespace you will have a big CPU overhead due system tablespace's db block checking which is on by default.

I've explained it here:

http://blog.tanelpoder.com/2008/09/02/oracle-hidden-costs-revealed-part2-using-dtrace-to-find-why-writes-in-system-tablespace-are-slower-than-in-others/

Otherwise, if by "replication being slow" you mean that the changes aren't pushed fast enough, I would run snapper on the push job session and see where its time is going.

--
Tanel Poder
http://blog.tanelpoder.com


On Sat, Oct 3, 2009 at 6:09 PM, A Joshi <ajoshi977_at_yahoo.com> wrote:



> Hi,

> I have adv replication (multi master) but it is slow : so I am thinking of

> going to streams. For speed. Do I need to keep anything else in mind before

> going to streams? Any other comparison between the two for other aspects

> like maintenance. How stable is streams now. I think initially with 9i it

> was not stable and lot of bugs/issues. I would be going from 10g to 9i. Any

> issues with that. Any info is apreciated. Thanks for help.

>

>

>

> --

> http://www.freelists.org/webpage/oracle-l

>

>

>



-- 
Tanel Poder
http://blog.tanelpoder.com

--
http://www.freelists.org/webpage/oracle-l

Received on Sun Oct 04 2009 - 09:13:09 CDT