Thank You So much for the clarification.
On Mon, Nov 1, 2021 at 3:57 PM Ls Cheng <exriscer@xxxxxxxxx> wrote:
Hi
AFAIK Flashback database does not wipe out contents from cell flash cache.
Thanks
On Mon, Nov 1, 2021 at 10:03 AM Lok P <loknath.73@xxxxxxxxx> wrote:
Thank you. Got it.
So is it correct to say that the cache warmup we are talking about here
is mainly DB buffer cache. And yes, we can ignore the first 30 minutes of
workload replay. Btw I have heard the storage cell flash cache needs many
hours to be populated with the required blocks , storage indexes etc during
the initial point. So my question was, if it's going to wipe out the flash
cache also in case of DB flashback ? Or as Pap mentioned these are
persistent storage so they won't get wiped off like DB buffer cache in case
of DB flashback to past point in time?
On Mon, Nov 1, 2021 at 3:28 AM Ls Cheng <exriscer@xxxxxxxxx> wrote:
Hi
I think you should capture RAT for at least 3, 4 hours of workload. In
the old days when load tests were using tools such as Mercury
Loadrunner there was a stage in the beginning which we called ramp-up which
is the warming up stage you are describing to bring in live-like
conditions. During ramp-up response times are higher and are taken into
account when analyzing the data.
So to simplify things, run AWR every 30 minutes and consider the first
30 minutes as your ramp-up stage.
Thanks
On Sun, Oct 24, 2021 at 12:32 PM Lok P <loknath.73@xxxxxxxxx> wrote:
Hi, We are planning to use the real application testing feature of
Oracle for capturing and replaying production workloads to see the actual
impact of one of our coming versions and hardware upgrades. We have one
question- As before each workload replay the RAT database has to be
flashed back to the point in time where we have captured the workload from.
So will that flashback, remove everything from the RAT DB buffer cache and
also everything will be wiped out from the storage server flash cache? And
in that case the replay may not mimic the exact impact as the cache warmup
will be adding additional overhead to the resource and time and thus it may
not be a good comparison of before and after upgrade behaviour of RAT
database. Can you please confirm if this is the correct understanding and
how we should replay then to avoid this cache warmup thing? And if any
other RAT system related resources can also deviate the figures?
Regards
Lok
