Hi,

What the Y-axis of the "Files I/O Rate" and "Rollback Transactions I/O Rate" mean ? Percent, tps, or anything else ? Where can I obtain more info about these information could mean ? Comments, please...

Tks in Adv,
Sbleck

It says right in the graph title: one of the following Transactions, Hits, Blocks, Reads/Writes, etc.., which is just a selected counter type.

The rate depends on the graph settings. If you click Tools/Options menu and go to Monitor tab page you can select graph refresh rate and how many data points to show. If you have, for example, refresh rate set to 10 seconds then the value you see on the Y axis is how many Y-values happened during this 10 seconds time interval. For instance if the Rollback Transactions graphs shows Y-value 50 this means that 50 transactions occurred during 10 seconds. Because the graph shows multiple data-points you can monitor the dynamics and see how your database performance is affected over a period of time.

Hope this helps.

: Hi,

: What the Y-axis of the "Files I/O Rate" and "Rollback
: Transactions I/O Rate" mean ? Percent, tps, or anything else ? Where
: can I obtain more info about these information could mean ? Comments,
: please...

: Tks in Adv,
: Sbleck

: It says right in the graph title: one of the following Transactions, Hits,
: Blocks, Reads/Writes, etc.., which is just a selected counter type.

Ok, but for some type is possible to encounter some doubts about what they really could mean...

: The rate depends on the graph settings. If you click Tools/Options menu and
: go to Monitor tab page you can select graph refresh rate and how many data
: points to show. If you have, for example, refresh rate set to 10 seconds
: then the value you see on the Y axis is how many Y-values happened during
: this 10 seconds time interval. For instance if the Rollback Transactions
: graphs shows Y-value 50 this means that 50 transactions occurred during 10
: seconds. Because the graph shows multiple data-points you can monitor the
: dynamics and see how your database performance is affected over a period
: of time.

Ok. I used the following configuration, in these options:

Monitor/Graph: Overall Performance
Timer Interval: 60 seconds (default)
Checkpoints: 15 (default)

And, now let me explain using some examples:

- 15 min. of Overall performance resulted:

- The topmost item were about 9 units, for "Files I/O Rate"
- The topmost item were about 5,000.00 units, for "Rollback Segments I/O Rate"

- Another test (1 day after) with 15 min. of Overall performance resulted:

- The topmost item were below 0,1 units, for "Files I/O Rate"
- The topmost item were about 3,5 units, for "Rollback Segments I/O Rate"

Now, I need to interpret these result what they really mean. Could you make some comments about this ?

Rgds,
Sbleck

I am sorry, I somehow missed your message yesterday. Please see my comments below

: Ok, but for some type is possible to encounter some doubts about what they
: really could mean...

: Ok. I used the following configuration, in these options: Monitor/Graph:
: Overall Performance
: Timer Interval: 60 seconds (default)
: Checkpoints: 15 (default)

: And, now let me explain using some examples: - 15 min. of Overall performance
: resulted: - The topmost item were about 9 units, for "Files I/O
: Rate"
: - The topmost item were about 5,000.00 units, for "Rollback Segments I/O
: Rate"

: - Another test (1 day after) with 15 min. of Overall performance resulted: -
: The topmost item were below 0,1 units, for "Files I/O Rate"
: - The topmost item were about 3,5 units, for "Rollback Segments I/O
: Rate"

The graphs show only real-time information collected during the sampling intervals. If you close a graph and the re-open it again (a minute later or next day, it doesn't really matter) the sampling starts all over. If you do not close the graph and allow it to stay open then you can use the horizontal dotted green line (high water mark) for checking the highest value reached during the monitoring process.

Some tips…. you can use View/Historical Data/Record menu to record data collected by real-time graphs and monitors and them use View/Historical Data/Playback menu to playback the recorded information. This way you can playback real-time snapshots recorded while you were away.

If you install and schedule DB Trends package it will periodically collect a number of system performance statistics automatically in the background (on the server) you can then view this performance data using Trends/Custom Trends reports and graphs available in the DB Monitor GUI. The advantage of this method is that DB Monitor GUI does not need to run all the time. You use it only to view and analyze the results of data collections.

: Now, I need to interpret these result what they really mean. Could you make
: some comments about this ?

: Rgds,
: Sbleck