• x8 PCI Express 3.0 to 12 Gb/s SAS + SATA interface
• Broadcom SAS 3108 PowerPC 476 Controller @ 1.2GHz
• Connect up to 240 physical drives via SAS expander in RAID mode
• Supports high-bandwidth applications with PCIe^® 3.0 connectivity
• Supports 12, 6 and 3Gb/s SAS and 6, 3Gb/s SATA data transfer rates
• Supports RAID levels 0, 1, 5, 6, 10, 50, 60 as standard: balance protection and performance for critical applications
• 2GB Onboard DDR3 Cache Memory for write-cache ability to improve performance
• SR-IOV (Single Root I/O Virtualization) supported with up to 16 VF (Virtual Functions)
• Fit into 1U/2U rack-mounted servers with low-profile form factor

This RAID add-on card features 2GB of onboard DDR3 cache memory to support write-back RAID caching. RAID caching is an excellent and cost-effective way to improve I/O performance by writing data to a controller’s cache before it is written to disk. Write-back cache improves application performance by storing write data to high performance cache memory during periods of heavy use. Where there is a break in user requests, the data is written from the cache memory to the storage array.

To protect against the loss of data being temporarily stored in cache memory before it has been written to disk, this RAID card can be combined with a Broadcom CacheVault CVM02 Flash Cache Protection Module. CacheVault technology prevents data loss by powering critical components of the card long enough to automatically transfer the cached data to a NAND flash module. Once power returns, the data is restored to the cache and normal operation resumes.

Write-Back Cache Protection

During normal write-back operation when data is written to the RAID card’s onboard cache memory (DRAM), the I/O is acknowledged as “complete” to the application that issued the write, and later the write is flushed to disk. If power is lost while write-back cache is enabled, the writes in DRAM may be lost. Since the controller has already acknowledged the I/O as complete, the application is unaware of the data loss.

Super Capacitor Technology Eliminates Hardware Maintenance Costs

Older generations of RAID controllers used lithium-ion based battery backup units. Over the life of a controller, the battery needed to be replaced numerous times, as it is only good for about 1.5 years. Furthermore, shipping and disposing lithium-ion batteries require special considerations and fees. The Broadcom CacheVault Protection Modules feature a super capacitor instead of lithium-ION batteries for back-up power, which virtually eliminates maintenance costs (does not need replacement over the life of the controller card), lowers total cost of ownership, and is more environmentally friendly.