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Date: Sun, 5 Nov 2023 21:27:35 -0700
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Subject: Re: Bypass qdiscs?
To: Stephen Hemminger <stephen@networkplumber.org>,
 John Ousterhout <ouster@cs.stanford.edu>
Cc: Andrew Lunn <andrew@lunn.ch>, netdev@vger.kernel.org
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From: David Ahern <dsahern@kernel.org>
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On 11/5/23 8:23 PM, Stephen Hemminger wrote:
> On Sat, 4 Nov 2023 19:47:30 -0700
> John Ousterhout <ouster@cs.stanford.edu> wrote:
> 
>> I haven't tried creating a "pass through" qdisc, but that seems like a
>> reasonable approach if (as it seems) there isn't something already
>> built-in that provides equivalent functionality.
>>
>> -John-
>>
>> P.S. If hardware starts supporting Homa, I hope that it will be
>> possible to move the entire transport to the NIC, so that applications
>> can bypass the kernel entirely, as with RDMA.
> 
> One old trick was setting netdev queue length to 0 to avoid qdisc.
> 

tc qdisc replace dev <name> root noqueue

should work