SANcentral Performance
The SANcentral Performance dialog box provides a global view of storage-related metrics and allows you to drill down to specific parameters of interest from anywhere in the management region of the pool, including management consoles. Real-time read/write information for the SAN region can be displayed per domain, per storage or application server, or per individual virtual volume mapping. Depending on the selected element in the left pane, you will see different performance information in the right pane. Using this information, you can view the access patterns of your system and determine information such as whether the cache is too small or large for efficient operations. (You can also obtain other performance metrics from Windows performance tools.)
Performance Toolbar
You can monitor storage servers by using the following Performance Tools. The icons take you, from left to right, to Cache Hits, Regionwide Cache, Channel Details, Channel I/O Rate, Scheduler, Regionwide Scheduler, Storage Pool Tools. To enable this toolbar, select a storage server in the left pane.
Here is the Performance window displaying information for the total region:
The right pane consists of four areas: I/Os, KBs, Cache, Polls. Click on an icon, folder, or individual storage or application server in the left pane to display performance information in the right pane. When you select the Storage Domain Servers or Domains folder, I/O information for all channels in the region will be displayed.
Editing Performance Dialog Boxes
Some performance displays allow you to click on the dial faces to change the scaling independently of the trend graphs (x10, x100, x1000). You can also change the scale of the trend graphs by typing a new number into the Graph Maximum field and pressing Enter.
Performance Displays
The tables below explain the information displayed in the SANcentral Performance tool. The information displayed varies and is dependent on the selection in the left pane:
I/Os Area |
Description |
Write IO/s |
Number of write operations per second. |
Read IO/s |
Each read is a Read Hit, Read Miss, or Read Pending. |
Total |
Total number of read and write I/Os. |
KBs Area |
Description |
Write KB/s |
Number of KBs of data written to the cache per second. |
Read KB/s |
Number of KBs of data read per second. |
Total |
Total number of KBs of data read and written. |
Bar |
Visual display showing the mode of the I/O; initiator or target. |
Cache Area |
Description |
Read IO/s |
Number of read operations per second. Each read is categorized:
|
Write IO/s |
Number of write operations per second. |
Bar |
Visual display reflecting the category of the read. |
Cache Devices |
The number of volumes opened by the cache. |
Polls Area |
Description |
Graph Maximum |
Enter the maximum number to use in your graph. |
Total (red graph line) |
Line displaying the total number of channel polls, includes productive and nonproductive. |
Productive (green graph line) |
Line displaying the productive number of polls, when the poller checks and discovers work to be done for the channel. |
Total Polls/s |
Total channel polls taken per second, includes productive and nonproductive. |
%Productive |
Percentage of productive polls to total channel polls per second. |
Domain Area |
Description |
Name |
Domain name. |
# Mappings |
Total number of mappings per domain. |