- Avoid main lock contention by trylock for if_start, if that fails,
schedule TX taskqueue for if_start
- Don't do direct sending if the packet to be sent is large, e.g.
TSO packet.
This change gives me stable 9.1Gbps TCP sending performance w/ TSO
over a 10Gbe directly connected network (the performance fluctuated
between 4Gbps and 9Gbps before this commit). It also improves non-
TSO TCP sending performance a lot.
Reviewed by: adrian, royger
Approved by: adrian (mentor)
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D5074
719d2f1ad5