* Rusty Russell (rusty@xxxxxxxxxxxxxxx) wrote: > On Thursday 09 October 2008 06:34:59 Mark McLoughlin wrote: > > From: Herbert Xu <herbert.xu@xxxxxxxxxx> > > > > If segmentation offload is enabled by the host, we currently allocate > > maximum sized packet buffers and pass them to the host. This uses up > > 20 ring entries, allowing us to supply only 20 packet buffers to the > > host with a 256 entry ring. This is a huge overhead when receiving > > small packets, and is most keenly felt when receiving MTU sized > > packets from off-host. > > There are three approaches we should investigate before adding YA feature. > Obviously, we can simply increase the number of ring entries. Tried that, it didn't help much. I don't have my numbers handy, but levelled off at about 512 and was a modest boost. It's still wasteful to preallocate like that on the off-chance it's a large packet. thanks, -chris _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
