content_image/982914.jpg
Figure 12-3 shows the read hit performance numbers. 

<img src='content_image/982914.jpg'>

The numbers that are shown in Figure 12-3 were obtained with 128 concurrent jobs in all runs, each job uses 32 KiB blocks, and QSAM BUFNO = 20. Before R 3.2, the volume size was 800 MiB (300 MiB volumes @ 2.66:1 compression). Since R 3.2, the volume size is 2659 MiB (1000 MiB volumes @ 2.66:1 compression). 

From a performance aspect, the architecture offers the following important characteristics: 

GLYPH<SM590000> With the selection of IBM Db2fi as the central repository in the TS7700, the TS7700 provides a standard Structured Query Language (SQL) interface to the data, and all data is stored and managed in one place. Db2 also allows for more control over performance. 

GLYPH<SM590000> The cluster design with virtualization node (vNode) and hierarchical data storage management node (hnode) provides increased configuration flexibility over the monolithic design. 

GLYPH<SM590000> The use of Transmission Control Protocol/Internet Protocol (TCP/IP) instead of FICON for site-to-site communication eliminates the requirement to use channel extenders. 

