enabling a total of two cards in a half-height server blade, and three cards in a full-height server blade and up to 6 in a double-high, double-wide server (BL680c).
The Gen8 adapter is provided in a c-Class Type B Mezzanine card form factor. It can only be installed in Type B mezzanine slots within the Gen 8 or later servers, enabling one IO Accelerator in a half-height Gen8 server.
The Type I mezz card and the Type B mezz card are distinguished by the mezzanine connector. The type B card is slightly larger than a Type I mezz card.
The amount of free RAM required by the driver depends on the size of the blocks used when writing to the drive. The smaller the blocks, the more RAM is required. The table below lists the guidelines for each 80GB of storage. For the latest information, see the QuickSpecs sheet to the HP IO Accelerator for HP BladeSystem c-Classat HP Customer Support (http://www.hp.com/support).
The Remote Power Cut Module for the c-Class blade mezzanine card provides a higher level of protection in the event of a catastrophic power loss (for example, a user accidentally pulls the wrong server blade out of the slot). The Remote Power Cut Module ensures in-flight writes are completed to NAND flash in these catastrophic scenarios. Without the Remote Power Cut Module, write performance is slower. Writes are not acknowledged until the data is written to the NAND module, thereby slowing performance. When the Remote Power Cut Module is installed, writes are acknowledged by the IO Accelerator controller to the driver. The IO Accelerator controller then completes the write to the NAND module.
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
Introduction 10
