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: <4ABA6F44.4000702@candelatech.com>
Date:	Wed, 23 Sep 2009 11:56:04 -0700
From:	Ben Greear <greearb@...delatech.com>
To:	Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@...el.com>
CC:	NetDev <netdev@...r.kernel.org>
Subject: Re: Getting physical packet counts with LRO enabled with ixgbe?

On 09/23/2009 11:50 AM, Peter P Waskiewicz Jr wrote:

>> That's a bummer.  I'm guessing you might get close to right on average with some
>> trivial math, but if someone is sending you pkts with size of 1000 and
>> your MTU is 1500, would there be any way to tell that the pkts were originally
>> 1000 bytes instead of 1500?
>
> Good point.
>
>> Next time you guys re-compile your hardware, please consider adding byte counters :)
>
> On 10G adapters, byte counters can skyrocket quickly, so we'd need to
> read them often to avoid them wrapping.  But I will forward your request
> to our HW design folks and see if they have other ideas to implement
> these counters and make them efficient.

It still takes a while to wrap 64-bit counters :)

But, you do have to read every 3 secs or so if you're using 32-bit counters.

This can be dealt with in user-space easily enough as long as polling
the NIC for counters is efficient.

Thanks,
Ben

-- 
Ben Greear <greearb@...delatech.com>
Candela Technologies Inc  http://www.candelatech.com

--
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

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ