netdev - Re: [net-next 1/2] qdisc: Allow qdiscs to provide backpressure up the stack.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20100826.223604.48516081.davem@davemloft.net>
Date:	Thu, 26 Aug 2010 22:36:04 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	greearb@...delatech.com
Cc:	netdev@...r.kernel.org
Subject: Re: [net-next 1/2] qdisc: Allow qdiscs to provide backpressure up
 the stack.

From: Ben Greear <greearb@...delatech.com>
Date: Thu, 26 Aug 2010 22:22:23 -0700

> On 08/26/2010 09:34 PM, David Miller wrote:
>> From: Ben Greear<greearb@...delatech.com>
>> Date: Thu, 26 Aug 2010 21:14:39 -0700
>>
>>> I'll look into the NET_XMIT_CN, but if that propagates backpressure up
>>> through mac-vlan, then something must know how to re-start the tx
>>> logic.
>>
>> It doesn't need to, as it drops and frees up the packet.
> 
> If there were 5 pkts in the socket buffer, and the attempt to
> send the first one caused NET_XMIT_CN, then
> based on your comment below about UDP being throttled, I assume
> the other 4 are kept until later?

It only has an effect on TCP, it causes it to decrease the
congestion window limits.

I did not state that it had any effect on UDP.  Just because I
talk about UDP later in my email doesn't mean the two things
are related.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html