tcp_isn_tick() / dummynet() callout madness ?

Soekris NET4501
Current kernel
WITNESS

Single user mode

10:55AM  up 17 mins, 1 user, load averages: 0.20, 0.15, 0.09

Sun Jan 30 10:56:05 UTC 2005

Callout accounting:
                     
count    1061761 time   67.148 func 0xc05573e0 dummynet()
count    1061762 time   56.688 func 0xc056c128 tcp_isn_tick()
count      10646 time    0.877 func 0xc04e193c 
count      10609 time    0.778 func 0xc04e193c 
count      10609 time    0.759 func 0xc04e193c 
count      10650 time    0.751 func 0xc0455408 
count      10608 time    0.751 func 0xc04e193c 
count       5326 time    0.324 func 0xc04f4fe0 
count      10651 time    0.323 func 0xc04d3f00 

We spend roughly 5% of the real time in those two callout functions,
probably in locking ?

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