3 Critical Storage Performance Architecture Considerations

Architecture matters and storage architecture is being optimized from many different directions to make it faster and cheaper, as detailed in the recent Baron’s article “Tech Vets Vie for New Storage Supremacy.” The article about four companies that are trying to develop the next generation of computing storage to be cheaper from its current $3.00 per gigabyte price point. Four different companies were highlighted:

• Skyera uses the cheaper MLC Flash chips to reduce costs to just $0.25 per gigabyte by sometime next year.
• Tegile uses system software, MLC chips and flash to bring prices down to about $1.10 per gigabyte.
• Maxta believes it can be even cheaper by using software defined storage.
• Nutanix converges the storage concepts by combining software, flash and disk.

These and other companies will continue the quest to make storage dramatically cheaper as the CPU chip speed plateaus, making I/O performance and I/O management critical for application success.  By reducing storage costs, these companies will allow us all to store everything.

The following three critical storage performance architecture items will help you position your DB2 systems for maximum performance and management flexibility.

1. Design your database tables and partitioning strategy for I/O priority tiers.  Last week I talked about designing your database tables with time considerations and maybe temporal dimensions.  Once designed, the different time or temporal dimensions need to have different storage groups, with appropriate attributes assigned that reflect their different I/O priorities.  These different I/O priorities need to be reflected across all the DB2 subsystem objects and the DB2 temporary work objects along with the different databases.  Remember to make the DB2 system the highest I/O priority so it can service the DB2 workloads.  Then the different databases and their temporal storage structures can be prioritized appropriately.  
   
   
2. Use all the components to prioritize your I/Os. DFSMS storage facilities, z/OS and UNIX operating system parameters, virtual machine prioritization, database object definitions, Work Load Manager (WLM) settings, and the buffer pool definitions need to be aligned to prioritize I/Os within any high performance environment. 
   
   This alignment and collaborative process with your systems programmer group and your DFSMS storage administration group determine the proper assignments for the newer faster storage and slower older storage needs to be verified.  Validating these DB2 definitions along with storage systems administrator’s settings are vital.  Once properly defined and verified, these DFSMS and DASD facilities and their volumes are critical to leverage for DB2 BACKUP SYSTEM mechanisms or cloning of DB2 subsystems. They can provide particular databases or certain objects with optimized backup and disaster recovery operations.
3. Start by understanding your current I/O attributes.  I/O within your environment is already prioritized through all these mechanisms mentioned earlier.  Research your current environment and start with the basics by understanding your opportunities to tune I/O access to different storage groups that are defined within your DB2 database tables and indexes. 
   
   Use standard DB2 for z/OS Catalog and DB2 LUW STOGROUP and DB2 object queries to expose the number of storage groups within your environment and the number of file extents that are being used.  Use this storage group information and extent information to begin to separate, prioritize, and optimize your I/O within your DB2 environment.

DB2 I/O performance is critical and understanding the mechanisms available to prioritize and optimize it are the beginning of improving the overall processing elapsed time of all of your DB2 applications.

Dave Beulke is a system strategist, application architect, and performance expert specializing in Big Data, data warehouses, and high performance internet business solutions. He is an IBM Gold Consultant, Information Champion, and President of DAMA-NCR, former President of International DB2 User Group, and frequent speaker at national and international conferences. His architectures, designs, and performance tuning techniques help organization better leverage their information assets, saving millions in processing costs.