I did find this: http://www.andrew.cmu.edu/user/ngm/15-823/project/Draft.pdf But there are several reasons this seems to be a dead-end route for Postgres: 1) It's limited to in-memory sorts. Speeding up in-memory sorts by a linear factor seems uninteresting. Anything large enough for a small linear speedup to be interesting will be doing a disk sort anyways. 2) It's limited to one concurrent sort. There doesn't seem to be any facility for managing the shared resource of the GPU. 3) It's limited to sorting a single float. Postgres has an extensible type system. The use case for sorting a list of floats is pretty narrow. It's also limited to 32-bit floats and it isn't clear if that's an implementation detail or a hardware limitation of current GPUs. 4) It uses a hardware-specific driver for Nvidia GPUs. Ideally there would be some kind of kernel driver which took care of managing the shared resource (like the kernel manages things like disk, network, memory, etc) and either that or a library layer would provide an abstract interface so that the Postgres code would be hardware independent. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com
