Storage Performance Analysis and Sizing for the IBM i host platform
Summary: How to perform storage performance analysis and sizing of ASP capacity and individual disks for an IBM i host system.
This article applies to
This article does not apply to
This article is not tied to any specific product.
Not all product versions are identified in this article.
Instructions
Management Summary:
The IBMi host platform has its own specific tools for collecting performance data from various system components, that is CPU, Main Store Memory (RAM), I/O-adapters, disks, so forth The collected performance data is useful for troubleshooting exercises, that is when performance problems are encountered. The data is also valuable for system administrators or managers for capacity-sizing tasks, trending analysis, so forth When DELL EMC IBMi specialty team Solution Architects are engaged in the presales phase for assistance in the design and sizing of the proposed IBMi storage solution, or when they are asked to perform a postmigration performance validation, the same data can be used for these purposes.
Collect, Create, Report, Analyze (>Design):
Collect:
The tools and options for the IBMi review and analysis tasks are available under the IBM Licensed Program that is entitled Performance Tools and it runs a Collection Services module in the background on the IBMi system. It is typically installed on every IBMi system, and the default performance collection is enabled to collect the relevant data in 15-minute intervals. It is preferred to set the collection rate to a 5-minute interval. This allows for more granular data points, better discovery of possible peak's or anomalies and also enables a 1:1 correlation with the performance data from the DELL EMC PowerMax storage array if needed, since this also runs at a default collection interval of 5 minutes. Typically the IBMi LPAR collects 24 hours worth of data, that is from 00:00 to 24:00 before starting to collect the data for the next day in a new collection file. By doing so, it contains the data for the entire day, in which an IBMi system typically does more transactional processing during the day and runs specific batch jobs or backups in the nightly and early hours. Obviously, when selecting a day for review or analysis, a recent day with relevant workload should be selected, or when looking for performance figures during peak utilization or workload, a period with highest activity can be selected, that is when an End-of-Month batch job is running. The collection file containing the raw collection data is of the *MGTCOL object type and typically resides in the QPFRDATA or QMPGDATA library. The object will be created with a name containing the Julian Day nr. and the time of creation, that is Q004000008 would be the collection file that started for January 4 on 00:00:08. The system administrator can set the retention time of the collection data, after which it is automatically deleted. The *MGTCOL file can also be saved into an IBMi SAVEFILE and sent to DELL EMC for analysis, that is over a secure folder on the DELL EMC FTP server. NOTE: depending on the size of the IBMi system and its resources and the collection interval and period, a single file can grow to several GB's in size. The data can then be loaded and restored on one of DELL EMC's IBMi lab systems for further analysis.
Create:
In order to use the collected data, the performance database files have to be available on the system where the analysis is performed. To re-create these files on another system, the command CRTPFRDTA has to be performed, where the wanted *MGTCOL file can be selected. Once the data has been re-created from the raw collection file, it can be used for review, analysis, reporting.
Report:
From the IBMi "green screen" user session, the Performance Tools menu provides options for using the performance collection data to create reports.
This can also provide simple histogram graphs for disk and CPU utilization, page faulting rate, so forth These graphs can be used to identify specific periods of interest, and detailed reports can be created for the selected period. Several predefined reports can be printed for an entire collection period or for a selected number of intervals, for the analysis of the disk storage workload, utilization and performance, the system- and resource- reports are used.
Analyze:
The previously mentioned basic reporting tools provide detailed information, but it is not easy to use for a more holistic view or correlation across various workload and performance metrics. IBM provided a tool for better graphical analysis, called PM400, which can also use the LPAR's collection services data for analysis. But as of September 2020, PM400 reached End Of Service Life(EOSL) and IBM's support for this tool was discontinued, but there are valid alternatives. Some commercial third-party software vendors have similar tools available but these come with purchase and licensing costs. Another alternative is to use the embedded tools in the IBMi operating system. IBM has developed Graphical User Interface (GUI) -based management tools for the IBMi platform. This started with the basic version of IBMi Operations Navigator or OpsNav, providing another method for performing specific systems management tasks, rather than using the green screen. In parallel, IBM developed the Systems Director Navigator for IBMi, this was similar but not the same. Today these tools have converged into a single GUI tool, called "IBM Navigator for i." This java-based tool uses a browser session that connects to the IP-address of the IBMi LPAR and communicates to specific system ADMIN jobs in the QHTTPSVR subsystem. It provides options to perform various systems management tasks and is also capable of providing detailed workload and performance graphs that are more useful than the basic textual reports. Below we see a sample of such graphical representation for the "Disk I/O Rates Overview."
This graph shows the disk I/O rates and the average service and response times for the ASP1 disks.
Design:
If the goal of the workload analysis and performance review is to size a new DELL EMC storage solution, the performance collection data from the customers existing IBMi LPARs provide adequate information. The IBMi Global Practice specialty team can be engaged to assist with such reviews or for sizing support to provide a best-practice storage design for the customers' IBMi platform (ibm_i_global_practice@emc.com).
The IBMi host platform has its own specific tools for collecting performance data from various system components, that is CPU, Main Store Memory (RAM), I/O-adapters, disks, so forth The collected performance data is useful for troubleshooting exercises, that is when performance problems are encountered. The data is also valuable for system administrators or managers for capacity-sizing tasks, trending analysis, so forth When DELL EMC IBMi specialty team Solution Architects are engaged in the presales phase for assistance in the design and sizing of the proposed IBMi storage solution, or when they are asked to perform a postmigration performance validation, the same data can be used for these purposes.
Collect, Create, Report, Analyze (>Design):
Collect:
The tools and options for the IBMi review and analysis tasks are available under the IBM Licensed Program that is entitled Performance Tools and it runs a Collection Services module in the background on the IBMi system. It is typically installed on every IBMi system, and the default performance collection is enabled to collect the relevant data in 15-minute intervals. It is preferred to set the collection rate to a 5-minute interval. This allows for more granular data points, better discovery of possible peak's or anomalies and also enables a 1:1 correlation with the performance data from the DELL EMC PowerMax storage array if needed, since this also runs at a default collection interval of 5 minutes. Typically the IBMi LPAR collects 24 hours worth of data, that is from 00:00 to 24:00 before starting to collect the data for the next day in a new collection file. By doing so, it contains the data for the entire day, in which an IBMi system typically does more transactional processing during the day and runs specific batch jobs or backups in the nightly and early hours. Obviously, when selecting a day for review or analysis, a recent day with relevant workload should be selected, or when looking for performance figures during peak utilization or workload, a period with highest activity can be selected, that is when an End-of-Month batch job is running. The collection file containing the raw collection data is of the *MGTCOL object type and typically resides in the QPFRDATA or QMPGDATA library. The object will be created with a name containing the Julian Day nr. and the time of creation, that is Q004000008 would be the collection file that started for January 4 on 00:00:08. The system administrator can set the retention time of the collection data, after which it is automatically deleted. The *MGTCOL file can also be saved into an IBMi SAVEFILE and sent to DELL EMC for analysis, that is over a secure folder on the DELL EMC FTP server. NOTE: depending on the size of the IBMi system and its resources and the collection interval and period, a single file can grow to several GB's in size. The data can then be loaded and restored on one of DELL EMC's IBMi lab systems for further analysis.
Create:
In order to use the collected data, the performance database files have to be available on the system where the analysis is performed. To re-create these files on another system, the command CRTPFRDTA has to be performed, where the wanted *MGTCOL file can be selected. Once the data has been re-created from the raw collection file, it can be used for review, analysis, reporting.
Report:
From the IBMi "green screen" user session, the Performance Tools menu provides options for using the performance collection data to create reports.
Analyze:
The previously mentioned basic reporting tools provide detailed information, but it is not easy to use for a more holistic view or correlation across various workload and performance metrics. IBM provided a tool for better graphical analysis, called PM400, which can also use the LPAR's collection services data for analysis. But as of September 2020, PM400 reached End Of Service Life(EOSL) and IBM's support for this tool was discontinued, but there are valid alternatives. Some commercial third-party software vendors have similar tools available but these come with purchase and licensing costs. Another alternative is to use the embedded tools in the IBMi operating system. IBM has developed Graphical User Interface (GUI) -based management tools for the IBMi platform. This started with the basic version of IBMi Operations Navigator or OpsNav, providing another method for performing specific systems management tasks, rather than using the green screen. In parallel, IBM developed the Systems Director Navigator for IBMi, this was similar but not the same. Today these tools have converged into a single GUI tool, called "IBM Navigator for i." This java-based tool uses a browser session that connects to the IP-address of the IBMi LPAR and communicates to specific system ADMIN jobs in the QHTTPSVR subsystem. It provides options to perform various systems management tasks and is also capable of providing detailed workload and performance graphs that are more useful than the basic textual reports. Below we see a sample of such graphical representation for the "Disk I/O Rates Overview."
Design:
If the goal of the workload analysis and performance review is to size a new DELL EMC storage solution, the performance collection data from the customers existing IBMi LPARs provide adequate information. The IBMi Global Practice specialty team can be engaged to assist with such reviews or for sizing support to provide a best-practice storage design for the customers' IBMi platform (ibm_i_global_practice@emc.com).
Affected Products
PowerMax, Symmetrix, VMAX, PowerStore, Dell EMC UnityArticle Properties
Article Number: 000196713
Article Type: How To
Last Modified: 02 Dec 2022
Version: 5
Find answers to your questions from other Dell users
Support Services
Check if your device is covered by Support Services.