Field values
This section explains the values stored in each field.
- Organization of this page
Delta
When data is collected as a cumulative value, delta is used to display the data as the amount by which the data has changed. For example, if the first performance data item collected is 3 and the second performance data item collected is 4, the cumulative value of 7 and a changed amount of 1 are stored. Whether the value in each field is a delta value is indicated in the Delta column of the Field table. Performance data collected by PFM - RM for Virtual Machine varies as shown in the table below.
Note that the delta value can be a negative value since it is a relative value that depends on the last data item.
Record type |
Delta |
Type of data |
Indicate delta value# |
Record value |
---|---|---|---|---|
PI record type |
Yes |
Real-time data |
Selected |
Displays the changed amount. |
Not selected |
Displays the changed amount. |
|||
|
-- |
Displays the changed amount. |
||
No |
Real-time data |
Selected |
Displays the value that was valid at the time of collection. |
|
Not selected |
Displays the value that was valid at the time of collection. |
|||
|
-- |
Displays the value that was valid at the time of collection. |
||
PD record type |
Yes |
Real-time data |
Selected |
Displays the changed amount. |
Not selected |
Displays the cumulative value. |
|||
|
-- |
Displays the cumulative value. |
||
No |
Real-time data |
Selected |
Displays the value that was valid at the time of collection. |
|
Not selected |
Displays the value that was valid at the time of collection. |
|||
|
-- |
Displays the value that was valid at the time of collection. |
- Legend:
-
--: Not applicable
- #
-
Selected means that the following GUI item is selected in the dialog box of PFM - Web Console:
-
Indicate delta value in the report wizard's Edit > Indication Settings(Realtime) window
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Indicate delta value in Indication Settings(Realtime) on the Properties page in the report window
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Note the following when performance data is being collected:
-
Before records of the PI record type can be saved, performance data must be collected at least twice.
Records of the PI record type collect performance data for each collection interval that was set in PFM - Web Console. However, performance data is not stored in the Store database at the time performance data collection is set in PFM - Web Console.
Since historical data of the PI record type contains data that requires the difference from the previously collected data (delta value), data from two collection intervals is required. Consequently, it takes a maximum of twice the set time before historical data is stored in the Store database.
For example, if the performance data collection interval is set to 300 seconds (5 minutes) at 18:32 on PFM - Web Console, the first data collection starts at 18:35 and the next data collection starts at 18:40. Historical data is created based on the data collected at 18:35 and 18:40, and is stored in the Store database at 18:40 (8 minutes after the setting time of 18:32).
-
A real-time report displays a value immediately when the first data is collected.
However, if a report requires previous data, 0 is displayed as the first value. The second and subsequent data collection operations differ depending on the report.
-
In the following cases, after the second data collection, the value in effect at the time of data collection is displayed:
-
Indicate delta value is not selected in the real-time report setting for the PI record type.
-
Indicate delta value is selected in the real-time report setting for the PD record type.
-
-
In the following case, after the second data collection, the difference between the first and second data is displayed. After the third data collection, however, the value in effect at the time of data collection is displayed:
-
Indicate delta value is selected in the real-time report setting for the PI record type.
-
-
If the monitored channel is rebooted while PFM - RM for Virtual Machine is starting, the collected data value may show a negative value. However, a value of 0 or greater will be displayed as the data difference for the second and subsequent data collections.