I use AUTO all the time and it is my go to IORM plan if I want to manage I/O
and allow the system to try to do it first. If that doesn’t produce the
desired result, then I will start to make my own plans, but it becomes very
difficult to get it right.
---
Thanks,
Shane Borden
sborden76@xxxxxxxxx
407-963-4883
On Nov 19, 2020, at 2:58 PM, Lok P <loknath.73@xxxxxxxxx> wrote:
It looks to me as if DB resource managers are purely made for CPU management,
and with that respect , I doubt it will be effective in managing the storage
cell I/O, and that is why IORM(IO resource manager) has come into picture.
But sadly it's not documented properly. And in most of the cases it says it
manages inter database workload only. But we are facing issues with intra
database workload management. I got below blog stating how AUTO objectives
for IORM fixed the issue of IO management. So has anybody used AUTO objective
for managing INTRA databases workload?
https://weidongzhou.wordpress.com/2013/08/23/awr-is-not-enough-to-track-down-io-problem-on-exadata/
<https://weidongzhou.wordpress.com/2013/08/23/awr-is-not-enough-to-track-down-io-problem-on-exadata/>
On Thu, Nov 19, 2020 at 2:29 AM Lok P <loknath.73@xxxxxxxxx
<mailto:loknath.73@xxxxxxxxx>> wrote:
We have one database with version 11.2.0.4 Exadata-X5 machine. We have IORM
objective kept as BASIC(which is default) and it's only one database in that
half RACK(~7 cell server) exadata cluster. We encountered performance issue
twice , where a ETL query doing FULL table/partition scan repetitively for
longer duration, causing the flash cache to be flooded with large reads and
the other low latency work load or small reads/index reads getting suffered
because of that, and so we had to kill the ETL query to let the low latency
workload perform in its normal speed.
I saw in a few blogs stating the IORM should be kept as AUTO and is
recommended. Wanted to understand from experts, if AUTO IORM setup is going
to help in such a situation, where we have only one database residing in the
exadata machine having multiple types of workloads(both OLTP and BATCH types
at same time) running in the same database? I am not seeing a clear
difference , how different is IORM objective AUTO from the BASIC incase of
single database IORM management?
