Overview of Hitachi Performance Monitor
Hitachi Performance Monitor enables you to monitor your storage system and collect detailed usage and performance statistics. You can view the data in lists and on graphs to identify changes in usage rates and workloads, analyze trends in disk I/O, and detect peak I/O times. For example, if there is a decrease in performance, such as delayed host response times, you can use Performance Monitor to discover the reason for the decrease and determine the actions to take to improve performance.
Performance Monitor collects data about storage system resources such as drives, volumes, and microprocessors as well as statistics about front-end (host I/O) and back-end (drive I/O) workloads. You can perform the following types of monitoring depending on the storage system:
- (VSP G1x00 and VSP F1500) You can perform both short-range monitoring and long-range monitoring. For long-range monitoring, data is collected constantly. For short-range monitoring, the data is collected when the Monitoring Switch is set to Enable, and you specify when and how often the data is collected.
- (VSP Gx00 models and VSP Fx00 models) Data is collected when the Monitoring Switch is set to Enable, and you specify when and how often the data is collected.
Using the Performance Monitor data, you can manage and fine-tune the performance of your storage system using the performance management software products.
Data collected by Performance Monitor
Performance Monitor allows you to collect the performance and usage statistics for your storage systems. Based on your storage system the following monitoring can be performed:
- (VSP G1x00 and VSP F1500) All statistics are available for short-range monitoring. Most of the storage system usage statistics are available for long-range monitoring. For details about the performance and usage statistics, see Monitoring data .
- (VSP Gx00 models and VSP Fx00 models) All statistics are available for monitoring. When you monitor the storage system, you control when the statistics are collected (in real time or during a specified period of time) and how often the statistics are collected (from once per minute to once every 15 minutes).
Cautions and restrictions for Performance Monitor
Cautions and restrictions for monitoring
- Performance monitoring switch
When the performance monitoring switch is set to disabled, monitoring data is not collected.
- Changing the
SVP time setting
If the SVP time setting is changed while the monitoring switch is enabled, the following monitoring errors can occur:
- Invalid monitoring data appears.
- No monitoring data is collected.
If you have changed the SVP time setting, disable the monitoring switch, and then re-enable the monitoring switch. Next, obtain the monitoring data. For details about the monitoring switch, see Starting monitoring.
- WWN monitoring
About the traffic monitoring between host bus adapters and storage system ports in Performance Monitor
You must configure some settings before the traffic between host bus adapters and storage system ports can be monitored. For details, see Adding new WWNs to monitor, Adding WWNs to ports, and Connecting WWNs to ports.NoteWhen you are using Server Priority Manager in Command Control Interface, you cannot perform the setting required for WWN monitoring.
- Parity group monitoring
To correctly display the performance statistics of a parity group, all volumes belonging to the parity group must be specified as monitoring targets.
- Storage system maintenance
If the storage system is undergoing the following maintenance operations during monitoring, the monitoring data might not be valid:
- Adding, replacing, or removing cache memory
- Adding, replacing, or removing data drives
- Changing the storage system configuration
- Replacing the microcode or firmware
- Formatting or quick-formatting logical devices
- Adding, replacing, or removing MP blade or unit
- Storage system power-off
If the storage system is powered off during monitoring, monitoring stops until the storage system is powered on again. Monitoring resumes when the storage system is powered on again. However, Performance Monitor cannot display information about the period while the storage system is powered off. Therefore, the monitoring data immediately after powering on again might contain extremely large values.
- microcode or
After the microcode or firmware is replaced, monitoring data is not stored until the service engineer releases the SVP from Modify mode. Therefore, inaccurate data might be temporarily displayed.
Cautions and restrictions for usage statistics
- (VSP G1x00 and
Retention of short-range and long-range usage statistics
Usage statistics for the last six months (186 days) are displayed in long-range monitoring, and usage statistics for up to the last 15 days are displayed in short-range monitoring. Usage statistics outside of these ranges are deleted from the SVP. In short range monitoring, results are retained for the last 1 to 15 days depending on the specified sampling interval. If the retention period has passed since a monitoring result was obtained, the previous result has been deleted from the SVP and cannot be displayed.
- (VSP Gx00 models and
VSP Fx00 models)
Retention of usage statistics
Usage statistics for up to the last 15 days are displayed in monitoring. Usage statistics outside of these ranges are deleted from the SVP.
- Statistics for periods of high I/O workload
If the host I/O workload is high, the storage system gives higher priority to I/O processing than to monitoring. If this occurs, some monitoring data might be missing. If monitoring data is missing frequently, use the Edit Monitoring Switch window to lengthen the sampling interval. For details, see Starting monitoring.
- (VSP G1x00 and
Volumes and CU ranges
The volumes to be monitored by Performance Monitor are specified by control unit (CU). If the range of used CUs does not match the range of CUs monitored by Performance Monitor, usage statistics might not be collected for some volumes.
- Reverse resync operations
When you run the CCI horctakeover command, the pairresync-swaps command for a UR pair, or the BCM YKRESYNC REVERSE command for a URz pair, the primary and secondary volumes are swapped. You can collect the before-swapped information immediately after you run any of the commands. Invalid monitoring data will be generated for a short time but will be corrected automatically when the monitoring data gets updated. The invalid data will temporarily be generated when the volume used for a secondary volume is used as a primary volume after a UR pair or URz pair is deleted.
(VSP G1x00 and VSP F1500) When SVP High Availability Feature is installed and the SVP is duplexed, if you switch the master SVP and the standby SVP, the long-range monitoring data is kept, but the short-range monitoring data is deleted. If you ask maintenance personnel to switch the master and standby SVPs for microcode upgrade or other maintenance purposes, execute Export Tool beforehand as necessary, and acquire the short-range monitoring data.
- Display of monitoring data immediately after monitoring starts or immediately after the sampling interval is changed
Monitoring data cannot be displayed within the first two sampling intervals after the monitoring starts or the sampling interval is changed because no monitoring data has accumulated. For instance, if the sampling interval is set or changed to 15 minutes, monitoring data is not accumulated for up to 29 minutes after this setting is made.
- Display of monitoring data during high
If the SVP is overloaded, the system might require more time than the sampling interval allows to update the display of monitoring data. If this occurs, a portion of monitoring data is not displayed. For example, suppose that the sampling interval is 1 minute, and the display in the Performance Management window is updated at 9:00 and the next update occurs at 9:02. In this case, the window (including the graph) does not display the monitoring result for the period of 9:00 to 9:01. This situation can occur when the following maintenance operations are performed on the storage system or on the Device Manager - Storage Navigator PC:
- Adding, replacing, or removing cache memory.
- Adding, replacing, or removing data drives.
- Changing the storage system configuration.
- Replacing the microcode or firmware.
Pool-VOLs of Thin Image, Dynamic Provisioning, and Dynamic Provisioning for Mainframe are not monitored.
- Margin of error
The monitoring data might have a margin of error.
Requirements for using performance functions
- Performance management products: The following software products are required for performance management operations.
- Hitachi Performance Monitor
- Hitachi Server Priority Manager
- Cache Residency Manager
- Hitachi Virtual Partition Manager
- Access: Administrator access for
Hitachi Device Manager - Storage Navigator or write access for the performance management software products is required to perform operations. Users without Administrator access or write access can only view the performance management information and settings. You need the specific administrator roles for each function:
- Performance Monitor: Storage Administrator (Performance Management)
- Server Priority Manager, Cache Residency Manager, Virtual Partition Manager: Storage Administrator (System Resource Management)
- License keys: The license keys for the performance management software products must be installed. For details about installing license keys, see the System Administrator Guide.
- Java: Java is required for Server Priority Manager and Cache Residency Manager. For details about installing Java and configuring Device Manager - Storage Navigator, see the System Administrator Guide.
- Hitachi Device Manager - Storage Navigator secondary windows: Secondary windows must be enabled before you use Server Priority Manager or Cache Residency Manager. Java and some settings of Hitachi Device Manager - Storage Navigator are required for the Hitachi Device Manager - Storage Navigator secondary window. For details, see the System Administrator Guide.
- Cache memory for Cache Residency Manager: Use of Cache Residency Manager might require additional cache memory in your storage system. For details, see Estimating cache size for Cache Residency Manager.
- Cache memory for Virtual Partition Manager: Use of Virtual Partition Manager might require additional cache memory in your storage system.