On Wed, Nov 16, 2016 at 4:58 PM, Ed Yu <edy@nwri.com> wrote:
> Hi,
>
> I am trying to find more information about the PgAdmin 4 Tabbed Browser. In
> the page, we have a couple of graphs and the documentation said:
>
> The Dashboard tab provides a graphical analysis of the usage statistics for
> the selected server or database:
>
> The Server sessions or Database sessions graph displays the interactions
> with the managed server or database.
> The Transactions per second graph displays the commits, rollbacks, and total
> transactions per second that are taking place on the managed server or
> database.
> The Tuples In graph displays the number of tuples inserted, updated, and
> deleted into the managed server or database.
> The Tuples out graph displays the number of tuples fetched and returned into
> the managed server or database.
> The Block I/O graph displays the number of transactions processed by the
> managed server or database.
>
> Is there any other documentation explain what those graphs means? More
> specifically, the last graph "Block I/O" does not make a whole lot of sense
> to me... What does Block I/O has to do with the number of transactions
> processed?
That's a documentation bug by the looks of it - I'll get it corrected.
It's actually the number of blocks read and hit by Postgres:
blks_read - Number of disk blocks read in this database/server
blks_hit - Number of times disk blocks were found already in the
buffer cache, so that a read was not necessary (this only includes
hits in the PostgreSQL buffer cache, not the operating system's file
system cache)
--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake
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