improved TSO interface needed
jfvogel at gmail.com
Mon Feb 26 07:25:37 UTC 2007
On 2/25/07, Kip Macy <kip.macy at gmail.com> wrote:
> The stack will send down chains where pkthdr.len > 65536 bytes - I'm
> also seeing it send down mbuf chains of 66 mbufs or more. I don't
> think all cards can handle an arbitrary number of descriptors being
> used for a single packet.
64K is the max, and I believe that is taking into account the headers.
What size are you seeing that is larger? Even if an mbuf chain comes
down that large, it does NOT form a single packet, it is packetized by
the hardware into MTU size, as I said, on the wire, ie as the receiver
sees it, its just a lot of packets. The only question is whether the
transmit hardware can handle it. Do you have eivdence of some
hardware that supports TSO in the driver that cant??
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