Monitoring Performance

Use the Performance Monitor to select and to monitor or to change the .

Starting Performance Monitoring

Use the following procedure to start performance monitoring:

Important:

The Performance Monitor does not dynamically update its display if any configuration changes (for example, creation of new virtual disks, change in virtual disk ownership, and so on) occur while the monitor window is open. The Performance Monitor window must be closed and then reopened for the changes to appear.
Using the Performance Monitor to retrieve performance data can affect the normal performance depending on the polling interval that you set. For more information, see Learn About Specifying Performance Monitor Settings.
If the storage array you are monitoring begins in or transitions to an Unresponsive state, an informational dialog is displayed, stating that the Performance Monitor cannot poll the storage array for performance data.

1	Select Storage Array >> Monitor Performance.
2	Click Settings to specify the virtual disks, RAID controller modules, or both to monitor and to specify the polling interval. To change the polling interval, choose a number of seconds in the spin box. Each time the polling interval elapses, the Performance Monitor re-queries the storage array and updates the statistics in the table.
3	Click Start. Important: For an accurate elapsed time, do not use the Set RAID Controller Module Clocks option while using the Performance Monitor. Values are displayed for the selected storage arrays in the Performance Monitor data table. The table is updated at the interval specified in the Polling Interval setting. Click Update to force an immediate poll of the storage array.
4	Click Stop to stop monitoring the storage array.

Saving Performance Data to a File

Click Save As on the Performance Monitor main dialog to save the currently displayed performance statistics.

Select an appropriate directory.

Type the file name of your choice in the File name field.

Note: The .perf extension is the default.

Select the file type of your choice in the Files of type text box.

File Type

Select this type when…

Report Format (ASCII text)

You want to save the data in a report form for viewing or printing.

Comma Delimited Format

You want to save the data in a form that can be imported into a commercial spreadsheet application for further analysis (most leading commercial spreadsheet applications recognize a comma delimiter and use the delimiter to import the data into spreadsheet cells appropriately).

Click Save.

About Storage Array Performance Data

The Performance Monitor data provides information about how your storage array is performing. The data is presented in eight columns, described in the following table. Use this data to make performance tuning decisions for your storage array.

Column

Description

Storage Arrays

The Storage Array column can display the following values:

RAID Controller Module, shown as RAID Controller Module in Slot A or B - Represents the totals for all virtual disks owned by the RAID controller module, not just the virtual disks presently selected for monitoring.
Virtual Disk, shown as Virtual Disk name, where Virtual Disk name is the name assigned to the virtual disk.
Storage Array Totals - Represents the totals for both RAID controller modules in an , regardless if one, both, or neither are selected for monitoring.

Total I/Os

The number of total I/Os performed by this storage array since Start was selected. When this number exceeds 99,999, it is displayed in thousands (K), beginning with 100 K until the number reaches 9999K, at which time it is displayed in millions (M). For amounts greater than 9999K but less than 100M, the value is displayed in tenths (for example, 12.3M).

Read Percentage

The percentage of total I/Os (previous column) that are read operations for this storage array. Write percentage can be calculated as 100 minus this value.

Cache Hit Percentage

The percentage of reads that are fulfilled by data from the cache rather than requiring an actual read from disk.

Current KB/second

The current KB per second, or transfer rate. Current means the number of KB per second since the last time that the polling interval elapsed, causing an update to occur, or since Update was selected.

Maximum KB/second

The highest value achieved by the current KB per second column for this polling session (since Start was selected).

Current IO/second

The current I/Os per second. Current means the number of I/Os per second since the last time the polling interval elapsed, causing an update to occur, or since Update was selected.

Maximum IO/second

The highest value achieved by the current I/Os per second column for this polling session (since Start was selected).

Column	Description
Storage Arrays	The Storage Array column can display the following values: RAID Controller Module, shown as RAID Controller Module in Slot A or B - Represents the totals for all virtual disks owned by the RAID controller module, not just the virtual disks presently selected for monitoring. Virtual Disk, shown as Virtual Disk name, where Virtual Disk name is the name assigned to the virtual disk. Storage Array Totals - Represents the totals for both RAID controller modules in an , regardless if one, both, or neither are selected for monitoring.
Total I/Os	The number of total I/Os performed by this storage array since Start was selected. When this number exceeds 99,999, it is displayed in thousands (K), beginning with 100 K until the number reaches 9999K, at which time it is displayed in millions (M). For amounts greater than 9999K but less than 100M, the value is displayed in tenths (for example, 12.3M).
Read Percentage	The percentage of total I/Os (previous column) that are read operations for this storage array. Write percentage can be calculated as 100 minus this value.
Cache Hit Percentage	The percentage of reads that are fulfilled by data from the cache rather than requiring an actual read from disk.
Current KB/second	The current KB per second, or transfer rate. Current means the number of KB per second since the last time that the polling interval elapsed, causing an update to occur, or since Update was selected.
Maximum KB/second	The highest value achieved by the current KB per second column for this polling session (since Start was selected).
Current IO/second	The current I/Os per second. Current means the number of I/Os per second since the last time the polling interval elapsed, causing an update to occur, or since Update was selected.
Maximum IO/second	The highest value achieved by the current I/Os per second column for this polling session (since Start was selected).

Monitoring Performance

Starting Performance Monitoring

Saving Performance Data to a File

About Storage Array Performance Data

Related Topics