[Make-wifi-fast] [Codel] fq_codel_drop vs a udp flood
eric.dumazet at gmail.com
Sun May 1 13:59:52 EDT 2016
On Sat, 2016-04-30 at 20:41 -0700, Dave Taht wrote:
> >>> 45.78% [kernel] [k] fq_codel_drop
> >>> 3.05% [kernel] [k] ag71xx_poll
> >>> 2.18% [kernel] [k] skb_release_data
> >>> 2.01% [kernel] [k] r4k_dma_cache_inv
> The udp flood behavior is not "weird". The test is wrong. It is so filling
> the local queue as to dramatically exceed the bandwidth on the link.
Well, just _kill_ the offender, instead of trying to be gentle.
fq_codel_drop() could drop _all_ packets of the fat flow, instead of a
It is too cpu intensive to be kind to the elephant, since under pressure
fq_codel_drop() needs to be called for every enqueue.
Really, we should not try to let inelastic flows hurt us.
I can provide a patch.
More information about the Make-wifi-fast