All of lore.kernel.org
 help / color / mirror / Atom feed
From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: "Timur Kristóf" <timur.kristof@gmail.com>
Cc: "michael.jamet@intel.com" <michael.jamet@intel.com>,
	"dri-devel@lists.freedesktop.org"
	<dri-devel@lists.freedesktop.org>
Subject: Re: Why is Thunderbolt 3 limited to 2.5 GT/s on Linux?
Date: Mon, 1 Jul 2019 14:44:53 +0300	[thread overview]
Message-ID: <20190701114453.GR2640@lahna.fi.intel.com> (raw)
In-Reply-To: <29c0d7a01f5b233ff3b68ad215f7ac9308f860db.camel@gmail.com>

On Fri, Jun 28, 2019 at 04:53:02PM +0200, Timur Kristóf wrote:
> On Fri, 2019-06-28 at 17:14 +0300, Mika Westerberg wrote:
> > On Fri, Jun 28, 2019 at 03:33:56PM +0200, Timur Kristóf wrote:
> > > I have two more questions:
> > > 
> > > 1. What is the best way to test that the virtual link is indeed
> > > capable
> > > of 40 Gbit / sec? So far I've been unable to figure out how to
> > > measure
> > > its maximum throughput.
> > 
> > I don't think there is any good way to test it but the Thunderbolt
> > gen 3
> > link is pretty much always 40 Gb/s (20 Gb/s x 2) from which the
> > bandwidth is shared dynamically between different tunnels (virtual
> > links).
> 
> That's unfortunate, I would have expected there to be some sort of PCIe
> speed test utility.
> 
> Now that I gave it a try, I can measure ~20 Gbit/sec when I run Gnome
> Wayland on this system (which forces the eGPU to send the framebuffer
> back and forth all the time - for two 4K monitors). But it still
> doesn't give me 40 Gbit/sec.

How do you measure that? Is there a DP stream also? As I said the
bandwidth is dynamically shared between the consumers so you probably do
not get the full bandwidth for PCIe only because it needs to reserve
something for possible DP streams and so on.
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

  reply	other threads:[~2019-07-01 11:44 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-28 10:23 Why is Thunderbolt 3 limited to 2.5 GT/s on Linux? Timur Kristóf
2019-06-28 10:32 ` Mika Westerberg
2019-06-28 11:08   ` Timur Kristóf
2019-06-28 11:34     ` Mika Westerberg
2019-06-28 12:21       ` Timur Kristóf
2019-06-28 12:53         ` Mika Westerberg
2019-06-28 13:33           ` Timur Kristóf
2019-06-28 14:14             ` Mika Westerberg
2019-06-28 14:53               ` Timur Kristóf
2019-07-01 11:44                 ` Mika Westerberg [this message]
2019-07-01 14:25                   ` Timur Kristóf
2019-07-01 14:28         ` Alex Deucher
2019-07-01 14:38           ` Timur Kristóf
2019-07-01 14:46             ` Alex Deucher
2019-07-01 15:10               ` Mika Westerberg
2019-07-01 14:54         ` Michel Dänzer
2019-07-01 16:01           ` Timur Kristóf
2019-07-02  8:09             ` Michel Dänzer
2019-07-02  9:49               ` Timur Kristóf
2019-07-03  8:07                 ` Michel Dänzer
2019-07-03 11:04                   ` Timur Kristóf
2019-07-04  8:26                     ` Michel Dänzer
2019-07-05  9:17                       ` Timur Kristóf
2019-07-05 13:36                       ` Alex Deucher
2019-07-18  9:11                         ` Timur Kristóf
2019-07-18 13:50                           ` Alex Deucher
     [not found]                             ` <172a41d97d383a8989ebd213bb4230a2df4d636d.camel@gmail.com>
2019-07-19 14:29                               ` Alex Deucher
2019-07-03 18:44                   ` Marek Olšák
2019-07-05  9:27                     ` Timur Kristóf
2019-07-05 15:35                       ` Marek Olšák
2019-07-05 16:01                         ` Timur Kristóf
     [not found]                         ` <8f0c2d7780430d40dd1e17a82484d236eae3f981.camel@gmail.com>
2019-07-18 10:29                           ` Michel Dänzer
2019-07-22  9:39                             ` Timur Kristóf
2019-07-23  8:11                               ` Michel Dänzer

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=20190701114453.GR2640@lahna.fi.intel.com \
    --to=mika.westerberg@linux.intel.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=michael.jamet@intel.com \
    --cc=timur.kristof@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.