*From:* Erik Trimble <[email protected]
GPUs sitting on the PCI-E bus are going to have this problem, and it's likely insurmountable.
In what context, ZFS or MD5 checksums? Over a year ago I did an experiment extracting what I believe was the 256-bit RAID-Z checksum calculation into a standalone user space program. Compared to a i7-920, a Quadro FX 4800 was much faster and this included the Gen2 x16 transport. Of course, the trick is to overlap the transport with compute so that data is always in flight.
HOWEVER, AMD *is* finally getting around to implementing a GPU in the same package as the CPU, so we'll shortly be able to see a combined CPU/GPU thing that sits in an AM3 socket (or, more likely, a C32 socket). There's even a possibility that AMD's talked about where an advanced GPU will live in a second CPU-style socket, with direct HT connections. This sort of design at least leads itself to being used as a co-processor, as it has direct low-latency connection to the memory contoller/bus.
Again, in the context of ZFS I don't believe data transport is the big problem to solve. I believe it is a kernel space API. Do we have any indication any of the GPGPU vendors (NVIDIA/ATI/Intel) will offer an API that can be called from kernel space? _______________________________________________ zfs-code mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/zfs-code
