Re: Flashback database

From: Stojan Veselinovski <stojan.veselinovski_at_gmail.com>
Date: Wed, 6 Feb 2013 09:33:57 +1100
Message-ID: <CALn1tDuJswzJtDkmVe_ykVYeADUx-i9r+K_PbxCER1LDA-FpkA_at_mail.gmail.com>

We use flashback in a number of our newer databases and have had no trouble with it. We don't generate 400G of redo but sit somewhere between 30-100 with spikes to 200. I haven't noticed any performance degradation.

I have used it extensively recently for testing code changes and performance tuning on snapshot standby databases. Creating restore points prior to major releases is a great way to be able to back out changes.

I did notice the event "flashback buf free by rvwr" a while ago but it didn't slow me down enough to investigate it. One thing to note is that if you have space in the FRA then Oracle tends to keep logs a lot longer than your retention target. In one db we have 24 hours retention yet we have 6 days of flashback logs occupying 100G.

In 11.2 you can turn it on and off without needing to shutdown the database and have it in mount state.

I personally think it's a great feature.

Stojan.

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Received on Tue Feb 05 2013 - 23:33:57 CET