Re: What MB/s is pulled from your buffer cache?

From: Martijn Bos <maboc_at_maboc.nl>
Date: Mon, 18 Feb 2013 14:40:56 +0100
Message-ID: <20130218134056.GA22356_at_app01.bos>



Hi,

Interesting subject (at least to me)

I'm on 11.2.0.1 on redhat(5).
When executing this query I get no rows returned.

Looking into v$statname I noticed this statistic is not there. Also the (online) documentation (11.2) didn't reveal much.

So now I wonder where to get more information on this statistic. I find out more than once that the statistic name is (to me) not quite descriptive, so I need some documentation to determine how to 'calculate' the 'logical read bytes from cache' statistic for 11.2.0.1.

So in short. 2 questions arise :
1 - Can anyone point me in the direction of some documentation 2 - Can anyone confirm that this statistic is available in 11.2.0.1 (or more presumably, that I'm mistaken)

Best Regards,
Martijn

On Tue, Feb 12, 2013 at 02:22:35PM -0600, Rich Jesse wrote: ...
...
> SELECT
> vs.value cache_read_bytes,
> vi.startup_time,
> ROUND(SYSDATE-vi.startup_time,2) uptime_days,
> (SYSDATE-vi.startup_time)*24*60*60 uptime_seconds,
> ROUND(vs.value / ((SYSDATE-vi.startup_time)*24*60*60)) bytes_per_sec
> FROM v$instance vi, v$sysstat vs
> WHERE vs.name = 'logical read bytes from cache';
...
...
> TIA!
>
> Rich
>
> p.s. The extra columns are for me to verify my calculations -- feel free to
> scrutinize with feedback!
>
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>

--
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Received on Mon Feb 18 2013 - 14:40:56 CET

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