HP PCIe IO Accelerators for ProLiant Servers - Manual (Page 10)

Introduction 10
Supported firmware revisions
Release Firmware revision
1.2.4 17350
1.2.7 36867 or 42014
1.2.8.4 43246
2.2 43674
Supported hardware
NOTE: ESX supports a maximum of five IO Accelerators or two IO Accelerator Duos per
system.
HP PCIe IO Accelerator minimum requirements:
• An open PCI-Express slot—The accelerator requires a minimum of one half-length, half-height slot
with an 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, only x4 signaling lanes must be connected for full performance.
NOTE: For PCIe IO Accelerators, using PCIe slots greater than x4 does not improve
performance.
• 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. This is the internal temperature of the
controller, and it is reported in fio-status. The IO Accelerator begins throttling write
performance when the junction temperature reaches 78 degrees C. If the junction temperature
continues to rise, the IO Accelerator shuts down when the temperature reaches 85 degrees 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). The following table lists the amount of RAM required per 80GB of storage space, using
various block sizes. The amount of RAM used in driver version 2.1 is significantly less than the
amount used in version 1.2.x.
Average block
size(bytes)
RAM usage (Megabytes)
per 80GB of storage for
version 2.x
RAM usage
(Megabytes) per
80GB of storage for
version 1.2.x
8,192 250 400
4,096 (most common) 400 800
2,048 750 1,500
1,024 1,450 2,900
512 2,850 5,600