Hey all, On yesterday's scheduler meeting I was raised the idea of bringing up the FPGA to the OpenStack as the resource, which than might be exposed to the VMs.
The use cases for motivations, why one want do this, are pretty broad - having such chip ready on the computes might be beneficial either for consumers of the technology and data center administrators. The utilization of the hardware is very broad - the only limitations are human imagination and hardware capability - since it might be used for accelerating execution of algorithms from compression and cryptography, through pattern recognition, transcoding to voice/video analysis and processing and all the others in between. Using FPGA to perform data processing may significantly reduce CPU utilization, the time and power consumption, which is a benefit on its own. On OpenStack side, unlike utilizing the CPU or memory, for actually using specific algorithm with FPGAs, it has to be programmed first. So in simplified scenario, it might go like this: * User selects VM with image which supports acceleration, * Scheduler selects the appropriate compute host with FPGA available, * Compute gets request, program IP into FPGA and then boot up the VM with accelerator attached. * If VM is removed, it may optionally erase the FPGA. As you can see, it seems not complicated at this point, however it become more complex due to following things we also have to take into consideration: * recent FPGA are divided into regions (or slots) and every of them can be programmed separately * slots may or may not fit the same bitstream (the program which FPGA is fed, the IP) * There is several products around (Altera, Xilinx, others), which make bitstream incompatible. Even between the products of the same company * libraries which abstract the hardware layer like AAL[1] and their versions * for some products, there is a need for tracking memory usage, which is located on PCI boards * some of the FPGAs can be exposed using SR-IOV, while some other not, which implies multiple usage abilities In other words, it may be necessary to incorporate another actions: * properly discover FPGA and its capabilities * schedule right bitstream with corresponding matching unoccupied FPGA device/slot * actual program FPGA * provide libraries into VM, which are necessary for interacting between user program and the exposed FPGA (or AAL) (this may be optional, since user can upload complete image with everything in place) * bitstream images have to be keep in some kind of service (Glance?) with some kind of way for identifying which image match what FPGA All of that makes modelling resource extremely complicated, contrary to CPU resource for example. I'd like to discuss how the goal of having reprogrammable accelerators in OpenStack can be achieved. Ideally I'd like to fit it into Jay and Chris work on resource-*. Looking forward for any comments :) [1] http://www.intel.com/content/dam/doc/white-paper/quickassist-technology-aal-white-paper.pdf -- Cheers, Roman Dobosz __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
