2.5 beta 1
 

Just wanted to say that the current beta driver is working phenomenally on my 2012 MacBook Air 11" connected to an Anker USB 3.0 dock (only one monitor connected currently).

using 2.5b1. Horrible performance and graphical corruption (same as with 2.4). Using external monitor with usb to hdmi dongle by unitek in general slows down whole system graphic performance wise. Attached 2 screenshots with examples of corruption.

And to give better understandin of what's happening when I plug in external display - without it whole system seems to be running at 60fps more or less, when plugging in the external everything slows down to 10fps (desktop switching, app switching etc.)

I'm not sure if switching to dell D3100 would be better option. It seems that it can handle 4k + 2xFullHD displays but i don't want to get stuck with expensive docking station and same issues....

Using El Capitan GM Beta and Macbook Pro 13" early 2015

Hi Rymek,

This kind of corruption usually happens when an application is trying to use hardware accelerated content on a virtual screen or when there is an issue with the software renderer for 3D content.

OS X does not support hardware acceleration on virtual displays so applications have to query display capabilities for each display and render accordingly.
The same applies to any USB or wifi screen with the exception of AirPlay that uses a proprietary interface.

Unless the public OS interfaces change I'm afraid we cannot do anything for this kind of problems. However application developers can ensure correct rendering if they are aware of these issues, I'd suggest to contact them.

About performance I think we can definitely improve the frame rate on our screens but any other slowdowns are again a systemic issue due to the fact that some screens are accelerated and others not.
You are welcome to join us in requesting better support for virtual screens from Apple!

Best regards,
Carlo

I'm not really sure if the performance problem is entirel apple's fault. I think it might be hardware issue. I've watched quite a few presentations of your products on youtube and the playback was pretty smooth (esp. Dell D3100 which streams in 4k, so that had to be smooth). In general my feeling is that external screen connected through the dongle is not really keeping up 60Hz.

I still wonder if on that Dell docking station it would be any better.

Hi Rymek,

Our USB3 product line does indeed allow for better performance than the USB2 line (not just because of the added bandwidth) but apart from that the key improvements have to come from SW.

So if you already have a USB 3 device I would not recommend to get another one on a performance basis.

In any case the message is clear: better performance needed. We'll be working on that.

Best regards,
Carlo

I've sent you debug log output through PM, not sure if you got it.

It's USB2.0 dongle actually, that's why i'm considering USB3.0

There are definitely problems in your logs that can lead to worse performance and higher CPU usage.
The driver cannot receive some key information about the screen from the OS but we don't yet know why this is happening on some systems.

I don't have any recommended workarounds for the moment I'm afraid.

Luckily we are investigating this class of issues right now and I will update you as soon as I have news.

About the device yes a USB3 model can offer better performance even if the Mac has USB2. Cannot recommend a specific brand or device though.

Best regards,
Carlo

Rymek,

Can you please try to open Terminal and type

sudo killall DisplayLinkUserAgent

You'll need to provide an admin password. This will force one part of the driver to restart and if the performance improves we'll have a good hint about the root cause.

Best regards,
Carlo

Nothing changed i'm afraid. Still the same after killing the agent. I'm assuming it restarted since it has new PID when i'm grepping it.

Thank you that's useful

Will keep you posted.

Carlo