On Thu, Jul 21, 2016 at 07:54:48AM +0200, Roman Dobosz wrote: > On Wed, 20 Jul 2016 10:07:12 +0100 > "Daniel P. Berrange" <berra...@redhat.com> wrote: > > Hey Daniel, thanks for the feedback. > > > > Thoughts? > > > > I'd suggest you'll increase your chances of success with nova design > > approval if you focus on implementing a really simple usage scheme for > > FPGA as the first step in Nova. > > This. Maybe I'm wrong, but for me the minimal use case for FPGA would > be ability to schedule VM which need certain accelerator from multiple > potential ones on available FPGA/fixed slot. How insane does it sound? > > Providing fixed, prepared earlier by DC administrator accelerator > resource, doesn't bring much value, beyond what we already have in > Nova, since PCI/SR-IOV passthrough might be used for accelerators, > which expose their functionality via VF.
IIUC, there's plenty of FPGAs which are not SRIOV based, so there's still scope for Nova enhancement in this area. The fact that some FPGAs are SRIOV & some are not though, is is also why I'm suggesting that any work related to FPGA should be based around refactoring of the existing PCI device assignment model to form a more generic "Hardware device assignment" model. If we end up having a completely distinct data model for FPGAs that is a failure. We need to have a generalized hardware assignment model that can be used for generic PCI devices, NICs, FPGAs, TPMs, GPUs, etc regardless of whether they are backed by SRIOV, or their own non-PCI virtual functions. Personally I'll reject any spec proposal that ignores existing PCI framework and introduces a separate model for FPGA. > > All the threads I've see go well off into the weeds about trying to > > solve everybody's niche/edge cases perfectly and as a result get > > very complicated. > > The topic is complicated :) Which is why i'm advising to not try to solve the perfect case and instead focus on getting something simple & good enough for common case. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
