SAP on IBM i: Reasons to upgrade your operating system release
The year 2017 is coming to its end soon, so it is time for New Year’s resolutions. Depending on your current IBM i release level, you may want to add the upgrade of the operating system to your list of things to accomplish in 2018. You probably know already that IBM has announced withdrawal of service for IBM i 7.1 and related software products effective April 30th, 2018 (ZP17-0256, 917-080, WP17-0057). Apart from that, there are many reasons to upgrade to IBM i 7.2 or IBM i 7.3 if you are not already there:
When upgrading to IBM i 7.2, SAP on IBM i users will see the following benefits:
- Improved database performance: With IBM i 7.2, the SQL optimizer was enhanced to consider the measured disk I/O performance rather than assumed fixed values. Complex SQL queries, as used e.g. in the SAP Business Warehouse application, can benefit from that by allowing a more precise calculation when choosing the best access plan. The benefit may not be as significant for short-running OLTP queries as used in SAP ERP.
- Improved file system performance with QFileSvr.400: With IBM i 7.2, you can configure to have more than one server job for the remote file system QFileSvr.400. This can help specifically, when several SAP systems share common directories (such as /usr/sap/trans) over QFileSvr.400. More information about this can be found in SAP Note 2202005.
- Removal of UPDATE limitations for partitioned tables: Prior to IBM i 7.2, partitioned tables did not allow UPDATE operations when the changes in a row would cause the row to move from one partition to another. This required careful planning when configuring partitioning for very large tables. With IBM i 7.2, this limitation has been removed, which is of particular use when partitioning non-BW tables. You can find more information about table partitioning for non-BW tables in SAP Note 2187681.
- Fair database locking: Most database operations only require weak locks (“shared”), which allow multiple processes to access a table at the same time. However, some operations require an exclusive lock to complete, e.g. when applying transports. Prior to IBM i 7.2, these exclusive locks would sometimes time out on a busy system because there were always some shared locks on the table. With IBM i 7.2 and the profile parameter dbs/db4/use_lock_queue, you can now configure that all locks need to “line up”, so that the exclusive lock gets a chance to be enforced.
- Database enhancements for Core Data Services (CDS): Beginning with SAP NetWeaver 7.40 SP05, SAP has introduced more features to the Open SQL interface in order to move load from the application server to the database and make better use of database capabilities. A lot of enhancements for Core Data Services have been implemented in IBM i 7.2, so you must be at least on IBM i 7.2 in order to use the CDS features with SAP NetWeaver 7.40 and SAP NetWeaver 7.5.
- Windows file server security: Do you remember the WannaCry ransomware attack of May 2017? As a result, Microsoft Security Bulletin MS17-010 (https://technet.microsoft.com/en-us/library/security/ms17-010.aspx) was released to disable the unsecure SMBv1 protocol on all Windows computers. The successor protocol SMBv2 is only supported with IBM i 7.2 and later (current PTF level required), but not with IBM i 7.1 or earlier.
When upgrading to IBM i 7.3, SAP on IBM i users will see all the benefits from IBM i 7.2 in addition to the following:
- Online backup of all IFS data: In the past, you would often see locking problems when saving IFS data while your SAP was running. Some files could not be saved because they were permanently locked by the active SAP system, and sometimes SAP background jobs would fail because their log file directory was locked by the backup. With IBM i 7.3, you can use the file and directory attributes *ALWCKPWRT and *INHCKPWRT to allow backing up all your IFS data while the SAP system keeps running. See SAP Note 825473 for more details.
- Showing the CPU clock rate in SAP performance tools: With IBM i 7.3 and SAP Host Agent 7.21 patch level 29 or later, you can now see the CPU clock rate in transaction ST06 or in the SAP Solution Manager through APM Introscope.
When planning the upgrade of the operating system to IBM i 7.2 or (preferably) IBM i 7.3, review the “IBM i Memo to Users” to verify that your hardware components are still current and for other details. For IBM i 7.2, you can find it at https://www.ibm.com/support/knowledgecenter/en/ssw_ibm_i_72/rzaq9/rzaq9.pdf, for IBM i 7.3, you can find it at https://www.ibm.com/support/knowledgecenter/ko/ssw_ibm_i_73/rzaq9/rzaq9.pdf. It may also be necessary to upgrade your SAP kernel to a minimum patch level. The requirements for each kernel release are documented in SAP Note 68440. In addition, SAP is maintaining SAP Notes with information about specific actions to take when going to a specific IBM i release. For IBM i 7.2, check SAP Note 2011710, for IBM i 7.3, check SAP Note 2299407.