On Tue, Apr 17, 2018 at 04:35:18PM -0400, Vlad Yasevich wrote: > On 04/02/2018 10:47 AM, Marcelo Ricardo Leitner wrote: > > On Mon, Apr 02, 2018 at 09:40:01AM -0400, Vladislav Yasevich wrote: > >> Now that we have SCTP offload capabilities in the kernel, we can add > >> them to virtio as well. First step is SCTP checksum. > > > > Thanks. > > > >> As for GSO, the way sctp GSO is currently implemented buys us nothing > >> in added support to virtio. To add true GSO, would require a lot of > >> re-work inside of SCTP and would require extensions to the virtio > >> net header to carry extra sctp data. > > > > Can you please elaborate more on this? Is this because SCTP GSO relies > > on the gso skb format for knowing how to segment it instead of having > > a list of sizes? > > > > it's mainly because all the true segmentation, placing data into chunks, > has already happened. All that GSO does is allow for higher bundling > rate between VMs. If that is all SCTP GSO ever going to do, that fine, > but the goal is to do real GSO eventually and potentially reduce the > amount of memory copying we are doing. > If we do that, any current attempt at GSO in virtio would have to be > depricated and we'd need GSO2 or something like that. > > This is why, after doing the GSO support, I decided not to include it. Gotcha. I don't think it will ever go further than what we have now. Placing data into chunks later is not really feasible/wanted, especially now with stream schedulers and idata chunks. Doesn't seem worth the hassle... we would have to support things like, "segment half of this message plus a third of this other one from that other stream." (in case it's round robin). Marcelo -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
