Post-Flash Solid State Storage Gets Real-er

HGST announced today that they are demonstrating an SSD that is based on Phase-Change Memory (PCM), one of the technologies competing to take over as flash runs out of steam. The selling point of the SSD is that it is extremely fast:

The demonstration shows unprecedented SSD performance levels that are achieved by utilizing a combination of HGST's new, latency-optimized interface protocols with next-generation non-volatile memory components.
The SSD demonstration utilizes a PCIe interface and delivers three million random read IOs per second of 512 bytes each when operating in a queued environment and a random read access latency of 1.5 microseconds (us) in non-queued settings, delivering results that cannot be achieved with existing SSD architectures and NAND Flash memories. This performance is orders of magnitude faster than existing Flash based SSDs, resulting in a new class of block storage devices. 

The SSD is based on 1Gb PCM chips. The new protocols that are needed to squeeze this performance out of PCIe were described by Dejan Vučinić et al in their paper DC Express: Shortest Latency Protocol for Reading Phase Change Memory over PCI Express at this year's FAST conference.