Re: Index Contention / Sequence Caching
From: Riyaj Shamsudeen <riyaj.shamsudeen_at_gmail.com>
Date: Mon, 17 Mar 2014 09:27:02 -0700
Message-ID: <CAA2Dszy-ADf9JkB0mbWr-BrzOEAHMgEbHn5ccHJRZwDk6MeJXA_at_mail.gmail.com>
Hello Stephen
In addition to Houri (and JL) has pointed out already, effect of a reverse key index is, to spread the values among ALL the leaf blocks of the index. So, the buffer cache(s) can be polluted with all these leaf blocks potentially. This problem is magnified if the number of leaf block in the index is huge.
Date: Mon, 17 Mar 2014 09:27:02 -0700
Message-ID: <CAA2Dszy-ADf9JkB0mbWr-BrzOEAHMgEbHn5ccHJRZwDk6MeJXA_at_mail.gmail.com>
Hello Stephen
In addition to Houri (and JL) has pointed out already, effect of a reverse key index is, to spread the values among ALL the leaf blocks of the index. So, the buffer cache(s) can be polluted with all these leaf blocks potentially. This problem is magnified if the number of leaf block in the index is huge.
Cheers
Riyaj Shamsudeen
Principal DBA,
Ora!nternals - http://www.orainternals.com - Specialists in Performance,
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