FCP X get sluggish and when quitting it says "canceling background tasks"

Every now and then FCP X gets sluggish. When I quit, I get the message "canceling background tasks" but before quitting there were no background tasks running. But it is probably the reason why FCP get slow.

What's wrong?

I have a MacPro 2013 with El Capitain 10.11.6 and FCP X 10.3.1

Hi Micha,

Could it be that this happens just after importing footage?
Besides the obvious background tasks like transcoding to proxies, to optimized media, exporting projects or background rendering, FCPX can be very busy with generating thumbnails and waveforms.
During these processes FCPX can react a bit sluggish, depending on the hardware specs.
You can check what's going on by clicking on the background task icon just above the browser window.

Hope this helps.
Robbert-Jan

Be sure to open the background tasks window and see what's going on.

It is not happening after import. The files were imported a few days ago. And it is also not generating thumbnails or waveforms, because I would see that in the background tasks window. Before I quit FCPX, I looked at the background task window and there was nothing going on. But when I immediately quit after looking, I get the message" canceling background tasks"

Hmmm, that's odd indeed.
Have you tried to make a new Library and copy the Event into the new Library.
When that is done, close all open Libraries except the one you just created.
When you now close FCPX, does it still say there are background tasks running?

Hoi Micha,

Both are related, but not in the way we are thinking about "background tasks".

The Background Tasks window only shows the most common tasks that FCP X performs while we work: rendering, exporting, optimizing, thumbnail and waveform generation, media management, clip analyzing, backup creation.

But FCP X also constantly writes to and reads from its databases (yes, there are more than just one for each Library). In average editing circumstances you will never notice this. It is done in the background, but it is not listed in the Background Tasks window because most of the times it's too fast to be able to see it.

Now, sometimes this data traffic can get jammed and then the app can begin to act slowly. We are still trying to find out the deeper cause of this: it could be an app-specific issue or an I/O speed issue that has nothing to do with the app itself. But it happens more frequently when doing complex editing (especially on longer projects with multicam and/or multichannel audio and/or tons of connected clips). OTOH, we have also seen it happen on short projects with lots of filters and titles. Anyway, in such cases, quitting FCP X can solve the data traffic jam and you will regain full editing performance after relaunch.

When you quit the app while the database hasn't been fully updated yet because the data stream is jammed, you will get the "cancelling background tasks" message. This means that FCP X will finish sending info to its database before quitting. If the data stream is really stuck, it will stop sending data and it will resume the database update at the next launch. The nifty trick here with FCP X is that you will never lose anything when quitting, even if the saving tasks aren't fully completed yet.

So yes, the message and the sluggishness are directly related. But until they find the real cause of this, there is not much you can do about it. The funny part is that it only seems to happen with very specific projects and media, and that the majority of FCP X users rarely or never see this problem. That's probably why it takes more time to get tot the bottom of this.

- Ronny

Hi Ronny,

Thanks for your elaborate answer. The project I am working on is indeed a long multicam project (in ProRes). Last week I had also a multicam project with separate multichannel audio. There I had the same problem too. I hope that it will be fixed in the coming update.

I think this is not a 10.3.1 thing. I also had this problem on 10.2 and earlier.

You are right, this has been happening for a longer time. I can assure you that we are looking into this very carefully. We see this issue happening more frequently in reality or documentary television projects involving multicam with multichannel audio and/or tons of connected clips. Will keep you updated.

- Ronny

Good points Ronny. FCPX is way faster for me than it ever has been but under certain circumstances I am seeing exactly these things. It seems to be related to certain plug-ins but is not consistent. I have send feedback and info to Apple.

Exactly, Nick. That is in fact one of the things we are looking into. From our testing, it seems like many of these slowdowns are caused by sending updated plugin, Filter and audio data to the SQL Lite databases. Too soon to come to a conclusion, but we are getting closer every day.

- Ronny

Your efforts are greatly appreciated!

Stabilization and optical flow will drag down if you do a lot of it, and won't show in background processes.

I didn't stabilization or and optical flowe and the only plugin I have is the coremelt trackX, but it wasn't used in this case.