netdev - Re: [PATCH v1 1/6] net: Generalize udp based tunnel offload

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: <CAKgT0Uf4GGmeMKHZsr4ZPmRWxSDT4hEHpLr03SczQBJ8Ei6E4A@mail.gmail.com>
Date:	Sun, 6 Dec 2015 10:44:54 -0800
From:	Alexander Duyck <alexander.duyck@...il.com>
To:	Tom Herbert <tom@...bertland.com>
Cc:	David Miller <davem@...emloft.net>,
	Hannes Frederic Sowa <hannes@...essinduktion.org>,
	John Linville <linville@...driver.com>,
	Jesse Gross <jesse@...nel.org>,
	Anjali Singhai Jain <anjali.singhai@...el.com>,
	Netdev <netdev@...r.kernel.org>,
	Kiran Patil <kiran.patil@...el.com>
Subject: Re: [PATCH v1 1/6] net: Generalize udp based tunnel offload

On Sun, Dec 6, 2015 at 8:31 AM, Tom Herbert <tom@...bertland.com> wrote:
>> The only spot I think you and I disagreed on was the approach.  I
>> don't know if the hard push back does anything but punish the users by
>> delaying the time needed to find a reasonable solution.  I really
>> think if we are going to get the hardware vendors to change their
>> behavior we have to create a market demand for it.  Having a bit of
>> marketable data showing the folly of this approach versus the 1's
>> compliment checksum would probably do more to encourage and/or shame
>> them into it than simply pushing for this based on engineering
>> opinion.
>>
> I don't know what "marketable data" means. But I do know that we're
> like 70 postings into this thread, into the third patch set regarding
> this, yet nobody has bothered to contribute any data on what these
> patches do and what the quantifiable benefits are with HW offload of
> these protocols. I would test this stuff myself, but I don't have
> access to any NICs with necessary support. If someone else can start
> testing and providing meaningful data it would be most helpful...

Here is an example of something kind of like what I am talking about:
http://www.mellanox.com/related-docs/whitepapers/CB_Intel_XL710.pdf

I have seen evidence of the gains first hand.  The biggest gain ends
up being the result of GRO, and you cannot make use of GRO without
some form of Rx checksum offload.

- Alex
--
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