And, (not but), if you're using sqlplus for this this traffic please be sure
you've set arraysize to something bigger than the default of 15.
Recommendations vary from 100ish to 1024ish. Last time I measured 1024 seemed
to work about best for a variety of situations and your mileage will vary by
too many infrastructure details for my measurements to be useful. I'm not aware
of any noticeable resource consumption or extra overhead from 1024.
Then, to answer Stefan's question, consider a profiler to tell you where the
problem lies.
mwf
-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Stefan Koehler
Sent: Tuesday, October 30, 2018 4:28 PM
To: Amir.Hameed@xxxxxxxxx; ORACLE-L
Subject: Re: IPC versus TCP performance
Hello Amir,
are you sure that this is a communication (latency) problem over the database
link and not an optimizer problem (e.g. bad execution plans) due to the
involved remote tables (distributed query)?
Best Regards
Stefan Koehler
Independent Oracle performance consultant and researcher
Website: http://www.soocs.de
Twitter: @OracleSK
"Hameed, Amir" <Amir.Hameed@xxxxxxxxx> hat am 30. Oktober 2018 um 14:01bit better.
geschrieben:
Hi,
I have two databases running on the same physical server. The OS is RHEL7.
Database A is 11.2.0.4 and is running as Active Data Guard. Database B is a
reporting database and is version 12.1.0.2. In the past, database A was
running on Solaris (four-node RAC) and we were using Oracle Streams to
replicate over 400 tables from this particular database over to database B.
We were also replicating tables from multiple other databases to database B
but that is beside the point for this discussion. After we converted database
A to LINUX, we decided to keep database B as the front-end and created
synonyms to access tables from database A (ADG) using DB links. We have also
setup IPC communication between A and B assuming that IPC would be faster
than TCP. Unless I have misconfigured IPC, so far the performance of
accessing database from B-to-A over a DB link is abysmal. Before I ask users
to start accessing A directly instead of going through B, I wanted to
understand the IPC communication a
--
In my scenario where both databases reside on the same physical server, is
there a way to optimize access from B-to-A over a DB link?
Thank you,
Amir