HP StorageWorks 4000 Compaq RAID Array 4000 Overview - Page 20

Compaq RAID Array 4000 Overview 20 Performance The RA4000 scales capacity and performance simultaneously. Each RA4000 adds processing power and cache to the overall system. The more hard drives an RA4000 contains, the higher the I/O performance scales. This fact is best illustrated by comparing the maximum number of I/O transactions per second per PCI server slot provided by an RA4000 to the maximum number provided by a ProLiant Storage System controlled by a Smart Array 3200 (SA3200) Controller11 (see Figure 9 and Table 2). In comparative tests performed in Compaq laboratories, test engineers used 2 KB random accesses to simulate an online transaction processing (OLTP) application. The accesses were 67 percent reads and 33 percent writes. The test results shown in Figure 9 indicate that a Compaq SA3200 Controller occupying a single PCI server slot can support approximately 939 simulated OLTP I/O per second. The RA4000, on the other hand, can support approximately 928 OLTP I/O per second using a single PCI server slot. Figure 9 shows that the SA3200 Controller gives better performance than the RA4000 up to a point. The RA4000 scales linearly far beyond the capabilities of SCSI technology. The high capacity and performance scalability make the RA4000 an ideal storage solution for large, power-hungry databases. 3000 RAID 5: I/O per PCI Slot Simulated Workload: OLTP (2 KB, 67% Read, 33% Write, 0% Sequential, 100% Random) 2500 2000 I/O per second 1500 1000 500 0 12 24 36 48 64 72 Number of Drives RAID Array 4000 Smart Array 3200 Figure 9. Performance scalability of a Fibre Channel system with a simulated workload 11 The SA3200 Controller is a SCSI device. ECG0205699A