netdev - Re: [PATCH] LRO ack aggregation

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: <20071120.142707.32641887.davem@davemloft.net>
Date:	Tue, 20 Nov 2007 14:27:07 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	rick.jones2@...com
Cc:	gallatin@...i.com, netdev@...r.kernel.org, ossthema@...ibm.com
Subject: Re: [PATCH] LRO ack aggregation

From: Rick Jones <rick.jones2@...com>
Date: Tue, 20 Nov 2007 11:45:54 -0800

> Sounds like one might as well go ahead and implement HP-UX/Solaris-like 
> ACK sending avoidance at the receiver and not bother with LRO-ACK on the 
> sender.
> 
> In some experiements a while back I thought I saw that LRO on the 
> receiver was causing him to send fewer ACKs already?  IIRC that was with 
> a Myricom card, perhaps I was fooled by it's own ACK LRO it was doing.

Linux used to do aggressive ACK deferral, especially when the ucopy
code paths triggered.

I removed that code because I had several scenerios where it hurt more
than it helped performance, and the IETF has explicitly stated in
several documents the (proven) perils of such stretch ACKs.
-
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