Somehow I missed this earlier this month–Gigabyte has announced a $50-ish PCI card that takes up to 4 DDR DIMMs and acts like a SATA RAMDISK. It has a battery that supposedly lasts 12-16 hours and will recharge via the PCI standby power line.
I’ve seen a bunch of people excited about using this as a boot disk or a Windows paging disk, but personally I’d love to see this used as an external journal for EXT3 filesystems. For some workloads, this would result in huge performance boosts for an amazingly small amount of cash. It’d be nice to have more battery life (36-72 hours would be ideal)–my personal record for a home power outage is 13 hours. All of my work-related outages have been brief, except for the facility in Manhattan that was dark for about a week in September of 2001.
via Ambient Irony
Update: I’ve been thinking about this, and the whole thing would be massively more useful with a couple small additions. First, add a Compact Flash socket to the board, and then update the ASIC that runs the board so it will copy the contents of the RAM onto the CF card after an hour or two without power. Then copy it all back when the power comes back up. You should be able to buy 1 GB of DRAM and 1 GB of CF flash for around $150; adding $100 for the PCI card give you 1 GB of seriously non-volatile memory for $250. I’d probably make them a standard feature in every server that I bought, just for the performance boost.