On Oct 30, 2013, at 9:38 AM, Daniel P. Berrange <berrange@xxxxxxxxxx> wrote: > On Wed, Oct 30, 2013 at 10:07:46AM -0400, Josh Boyer wrote: >> Hi All, >> >> I realize the WG is just forming up and you have a lot of other items >> to cover for now, but I wanted to get this sent out and have people >> start thinking about it sooner rather than later. >> >> The kernel team has heard in the past that the Cloud group would like >> to see something of a more minimal kernel for usage in cloud images. >> We'd like to hear the requirements for what this smaller image would >> need to cover. >> >> Right now, a default x86_64 kernel package on f20 is ~134MB installed. >> Most of that is device drivers installed in /lib/modules/`uname -r`/. >> The vmlinux binary is about 5MB and the initramfs (which is created >> at install time and can actually vary quite widely depending on >> various things) is about 11MB. Drivers can be trimmed to a degree, >> but please keep in mind that the kernel is already relatively small >> for the functionality it provides. For example, it is not much bigger >> than glibc-common (119MB). >> >> So, some caveats to keep in mind while you're thinking about this: >> >> 1) We're mostly talking about packaging here, not building a separate >> cloud kernel package or vmlinux. The kernel team really wants to have >> a single vmlinux across the 3 products if at all possible. We can't >> scale to much else. >> >> 2) What usecases is the cloud image going to cover? E.g. is it just >> virtio stuff, or will it also fit PCI passthru (which then requires >> drivers for those PCI devices)? > > FWIW, OpenStack cloud now supports use of PCI passthrough for guests, > so looking at the most general cloud case, we can't remove all the > non-virtio stuff. Most common PCI passthrough usage will likely be > for SRIOV NIC devices, with others more niche use-cases. > I second Daniel's comments here. In fact, in Icehouse the PCI passthrough support is likely to get better, there is a lot of interest for this especially in the NFV area. NICs are the most likely area of interest here, but I know Intel was also interested in graphics devices and passthrough as well. Thanks, Kyle >> 3) What are the common >> provisioning requirements that are driving the >> size reduction? (See comment about glibc-common. I would think >> change is needed in multiple packages, not just the kernel.) >> >> 4) Other "cloudy" stuff that I'm entirely unaware of that might be >> relevant. Explain it to me like I'm a child. > > Does anyone have an accurate report on where physical space in the > current cloud image goes to ? Just doing a 'du' on the cloud image > is only giving logical disk space, which doesn't correspond directly > to physical image space, due to differing compression ratios for > different types of content. > > Daniel _______________________________________________ cloud mailing list cloud@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/cloud Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
