Design Article
Computer & Storage Innovations - Battery-free, FPGA-based RAID cache solution
David McIntyre, Altera Corporation
2/17/2010 3:54 PM EST
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| David McIntyre Altera Corporation |
Increased data processing and storage demands are challenging traditional ways of maintaining data integrity in data centers. Increasing performance demands from applications in enterprise finance and Web 2.0 coupled with green environmental requirements are causing data center designers to look for more cost-effective, alternative approaches to today's battery-backed data recovery systems.
RAID adapter cards, a critical component of data center servers and storage complexes, traditionally rely on battery charged recovery circuitry to preserve the integrity of data during server power outages. Burdened by hazardous disposal and total cost of ownership (TCO) issues like field maintenance, system designers are looking for battery-free RAID adapter solutions that are more power efficient without impacting performance and data integrity specifications.
A battery-free RAID adapter design approach for protecting and restoring data during such power conditions is discussed in this article. Advancements in FPGA, flash memory, and capacitor technologies have enabled a lower power, nonvolatile memory backup solution that supports a battery-free environment and the benefits thereof. This article provides an overview of the supporting component technologies that can support such an environmentally-friendly data recovery solution.
Green Trends for Enterprise Data Centers
Increasing data center performance demands under constrained power budgets are creating management issues in power management, system cooling costs, and preservation of data integrity. These factors further contribute to the TCO of running these data centers. In addition, regulatory agencies are mandating green standards that stipulate data center power reductions and strict rules for battery materials disposal.
Power outages across server farms can result in data loss or even worse, undetected error conditions within the host application. To remedy these problems, companies have developed RAID adapter cards that provide a data recovery mechanism during such power outages. The issue with current RAID adapter products is that they are powered by batteries. The table below addresses many of the constraints associated with battery back up systems.
 Power Constraints Associated with Battery Back Up Systems Click on image to enlarge. |
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0xC0FFEE
2/18/2010 10:54 AM EST
We did a board like this about 6-7 years ago - SpartanIIe FPGA with PCI, SDRAM, NAND flash and a supercap backup circuit to hold up the ram long enough to dump it's contents into NAND with CRCs across everything. Nothing new under the sun...
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andyzg
2/18/2010 12:01 PM EST
didn't intel around 1984 have a combined SRAM & EEPROM chip that was able to save its SRAM contents to EEPROM upon PowerFail# ?
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Dr DSP
8/8/2010 9:00 PM EDT
It seems to me that in this design the processor outside the FPGA could be replaced with a programmable power management device- perhpas like a Lattice Power Manager II. It would provide the power monitoring, power ramp-up/down, trimming and hot swap (Does the board need hot swap capability? My guess is yes.), redundant power OR-ing, and watch-dog functions. There is even IP for fault logging using an external SPI Flash device. Perhaps the author could expand on this excellent article and dig into the power management aspects of the card a bit more. There might be some synergy with the rest of the design.
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