HP c-Class Vmware manual 192 096 048 12.4 GB 024 11.6 GB 15.7 GB 24 GB Introduction

The IO Accelerators (QK761A, QK762A, and QK763A) for Gen 8 BladeSystem c-Class have the power cut functionality embedded on the card. They offer the protection without requiring the remote power cut module.

NOTE: The Remote Power Cut Module is used only in the AJ878B and BK836A models. Without the Remote Power Cut Module, write performance is slower.

HP PCIe IO Accelerator minimum requirements

•An open PCI-Express slot—The accelerator requires a minimum of one half-length, half-height slot with a x4 physical connector. All four lanes must be connected for full performance. HP PCIe IO Accelerator Duo requires a minimum of a full-height, half-length slot with an x8 physical connection. If your system is using PCI 1.1, all x8 signaling lanes must be connected for full performance. If your system is using PCI 2.0, for full performance you only have to connect x4 signaling lanes.

NOTE: For PCIe IO Accelerators, using PCIe slots greater than x4 does not improve performance.

NOTE: The power cut feature is built into PCIe IO Accelerators; therefore, no Remote Power Cut Module is necessary.

•300 LFM of airflow at no greater than 50°C. To protect against thermal damage, the IO Accelerator also monitors the junction temperature of its controller. The temperature represents the internal temperature of the controller, and it is reported in fio-statusreport. The IO Accelerator begins throttling write performance when the junction temperature reaches 78°C. If the junction temperature continues to rise, the IO Accelerator shuts down when the temperature reaches 85°C.

NOTE: If you experience write performance throttling due to high temperatures, see your computer documentation for details on increasing airflow, including fan speeds.

•Sufficient RAM to operate—The amount of RAM that the driver requires to manage the NAND flash varies according to the block size you select when formatting the device (filesystem format, not low-level format). For a virtual machine using an IO Accelerator directly (using PCI pass-through), consult the user guide for the installed operating system. The following table lists the amount of RAM required per 100GB of storage space, using various block sizes. The amount of RAM used in driver version 3.0 is significantly less than the amount used in version 1.2.x.

Average block size	RAM usage for each 80	RAM usage for each 100	Minimum system RAM
(bytes)	GB IO Accelerator	GB IO Accelerator	requirement for 320 GB
	(Megabytes)	(Megabytes)	MezzIO Accelerator*
8,192	250	280	1 GB
4,096	400	530	1.6 GB
2,048	750	1,030	3 GB
1,024	1,450	2,000	5.8 GB
512	2,850	3,970	11.4 GB

Average block size	Minimum system RAM	Minimum system RAM	Minimum system RAM
(bytes)	requirement for 640 GB	requirement for 785 GB	requirement for 1.2 TB
	MezzIO Accelerator*	MezzIO Accelerator*	MezzIO Accelerator*
8,192	2 GB	2.2 GB	3.4 GB
4,096	3.2 GB	4.2 GB	6.4 GB
2,048	6 GB	8.1 GB	12.4 GB
1,024	11.6 GB	15.7 GB	24 GB

Introduction 10