From: Andrew Lunn <andrew@lunn.ch>
To: Waldemar Rymarkiewicz <waldemar.rymarkiewicz@gmail.com>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>,
Florian Fainelli <f.fainelli@gmail.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Network cooling device and how to control NIC speed on thermal condition
Date: Mon, 8 May 2017 16:02:25 +0200 [thread overview]
Message-ID: <20170508140225.GD19995@lunn.ch> (raw)
In-Reply-To: <CAHKzcENk8USj1kjFco=a+vdXeX-FycM1G4hPm6JnotEUtNi99Q@mail.gmail.com>
> However, the fact is that PHYs having active 1G/s link generate much
> more heat than having 100M/s link independently from network traffic.
Yes, this is true. I got an off-list email suggesting this power
difference is very significant, more so than actually processing
packets.
> All cooling methods impact host only, but "net cooling" impacts remote
> side in addition, which seems to me to be a problem sometimes. Also,
> the moment of link renegotiation blocks rx/tx for upper layers, so the
> user sees a pause when streaming a video for example. However, if a
> system is under a thermal condition, does it really matter?
I don't know the cooling subsystem too well. Can you express a 'cost'
for making a change, as well as the likely result in making the
change. You might want to make the cost high, so it is used as a last
resort if other methods cannot give enough cooling.
Andrew
next prev parent reply other threads:[~2017-05-08 14:02 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-25 8:36 Network cooling device and how to control NIC speed on thermal condition Waldemar Rymarkiewicz
2017-04-25 13:17 ` Andrew Lunn
2017-04-25 13:45 ` Alan Cox
2017-04-28 8:04 ` Waldemar Rymarkiewicz
2017-04-28 11:56 ` Andrew Lunn
2017-05-08 8:08 ` Waldemar Rymarkiewicz
2017-05-08 14:02 ` Andrew Lunn [this message]
2017-05-15 14:14 ` Waldemar Rymarkiewicz
2017-04-25 16:23 ` Florian Fainelli
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170508140225.GD19995@lunn.ch \
--to=andrew@lunn.ch \
--cc=f.fainelli@gmail.com \
--cc=gnomes@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=waldemar.rymarkiewicz@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).