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From: Paul Emmerich <emmericp@net.in.tum.de>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] Polling too often at lower packet rates?
Date: Fri, 10 Apr 2015 03:05:13 +0200	[thread overview]
Message-ID: <DBA1A0E4-76B5-44F9-8272-50F1027A318E@net.in.tum.de> (raw)
In-Reply-To: <9DF6C88A-AD12-4B04-899C-23C30FA760F1@net.in.tum.de>

Paul Emmerich <emmericp@net.in.tum.de> wrote:

> Stephen Hemminger <stephen@networkplumber.org> wrote:
> 
>> Your excess polling consumes PCI bandwidth which is a fixed resource.
> 
> I doubt that this is the problem for three reasons:
> 

4th: polling should not cause a PCIe access as all the required information is written
to memory by the NIC [1].

I only noticed that after I tried to measure the PCIe bandwidth caused by polling an X540
NIC... the result was 0 MBit/s ;)


Paul

[1] 82599 and X540 data sheets, Table 1-9

  reply	other threads:[~2015-04-10  1:05 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-08 16:35 Aaron Campbell
2015-04-08 18:00 ` Stephen Hemminger
2015-04-09 18:26   ` Aaron Campbell
2015-04-09 21:24     ` Stephen Hemminger
2015-04-10  0:42       ` Paul Emmerich
2015-04-10  1:05         ` Paul Emmerich [this message]
2015-04-08 19:11 ` Ananyev, Konstantin

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