> From: Stephen Hemminger [mailto:step...@networkplumber.org] > Sent: Sunday, 21 January 2024 18.08 > > On Sun, 21 Jan 2024 06:32:42 +0100 > Morten Brørup <m...@smartsharesystems.com> wrote: > > > I suppose that reducing mbuf->nb_segs from 16 to 8 bit is realistic, > considering that a maximum size IP packet (64 KB) is unlikely to use > more than 64 plus some segments. Does anyone know of any use case with > more than 255 segments in an mbuf? > > There is the case of Linux internally using super large IPv6 (and now > IPv4) frames. > See RFC 2675 IPv6 jumbograms > > https://netdevconf.info/0x15/slides/35/BIG%20TCP.pdf
Just took at brief look at it... I suppose something similar could grow into DPDK, so we are probably better prepared by leaving nb_segs at 16 bit. Then the proposed optimization falls to the ground. :-( Thanks for valuable feedback, Stephen. :-)
