TSO for IPv6 traffic

Network related discussions (including general TCP/IP stuff, routing, etc).

TSO for IPv6 traffic

Postby shreyasbforu » 20 Oct 2010, 23:36

Looking at the FreeBSD networking stack, TSO is not asked for outgoing IPv6 packets

CSUM_TSO is not set for IPv6 packets going out even when driver advertises IFCAP_TSO6. Any reasons why TSO over IPv6 is not supported ?
Any idea as to what work is involved in making this happen ?

Thanks in advance.
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Postby SirDice » 21 Oct 2010, 11:48

Andre wrote that TSO for IPv4 and IPv6 is always enabled or disabled together. But IPv6 currently lacks a pseudo-header checksum function and thus doesn't support TSO yet.

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Postby phoenix » 21 Oct 2010, 15:36

Search the freebsd-current mailing list for this week, specifically a thread with subject "IPV6 Checksum offload and TSO6", for a dicsussion of this topic. It appears that hardware is available that supports these functions (Intel), but the network stack doesn't support the features yet. A couple of coders are considering working on this in November.

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Postby acheron » 21 Oct 2010, 15:38

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