FCPX makes computer useless during timeline renders

Hi guys

After years of "pleasure/pain" editing on a Mac Mini, I purchased a 2nd hand MPBr (late 2013, 16Gb Ram)

As expected, the renders are indeed much faster than on the mini.

However, the big disappointment is that during (GPU heavy) renders, OSX becomes so slow that I can't do anything else during render.

Ironically, the Mac Mini did not behave like this... it was just slow, but did not saturate OSX.

Is there anything I can do in your opinion ?

Thanks !!!!

I have a MBP about that same year, and I don't experience this. But, there are several factors that come in to play here. I'm using a T'bolt drive for my Libraries and media. So, here's what we need to know in order to move forward.

- Are Libraries and media on system drive, or on external drive?
- If external drive, what type, size?
- On all drives, what percentage is currently left as free space?
- What format/codec are the clips you're editing?
- OS X and FCPX versions?
- Are you using an external monitor?

Personally I consider going from a Mac Mini to a laptop not an improvement. But then, machine specs are necessary to make a definitive conclusion.

Hi Ben

You're right about the improvement, but at least this MBP has a GPU. Anyway, I had no choice as I needed to go mobile, and budget is limited.

- Are Libraries and media on system drive, or on external drive?
External drive, portable (mobility needed)

- If external drive, what type, size?
LacieRug 500GB 3.0

- On all drives, what percentage is currently left as free space?
HD: 70Gb free / 500Gb
External: 238 free / 405Gb

- What format/codec are the clips you're editing?
ProRes HQ 422, 4K, with subtitles on top of it. no effects

- OS X and FCPX versions?
10.10.5
10.2.1
15inche, 2,3Ghz i7, 16Gb Ram, NVIDIA GeForce GT 750M 2048 MB

- Are you using an external monitor?
No

Just to clarify, FCPX reacts really well during editing. It is exporting/rendering, also with Compressor, that drives the computer to an extreme slowness (I can't even type text in textedit)

Thank you !

OK, internal drive is close to full. 50 GB is your limit of free space to be safe on that. Once a drive has less than that amount of free space, it can slow down. Plus have a ton of other strange symptoms that don't normally make sense.

4K on a laptop, that's pushing it. I've worked with 4K on occasion on mine, and with a T'bolt SSD drive, and I still had to use proxy media. I say make proxies and edit with that. And titles are intensive to render or export.

I'd also do a few things just to verify everything is up to snuff.
- Run Disk Utility to repair all drives.
- Trash pref files for FCPX.
- Run Disk Warrior to repair the directories on all drives.

That's about all you can do.

Also remember that the larger the drive, the faster it usually is. Look into a very large spinning disk USB 3.0 drive.

I'll assume that 400 GB external is an SSD?

Yeah, for 4K and HQ, I'm not surprised. Laptops don't have the most powerful GPUs. Not sure if there's anything you can do to make it faster, short of getting a T'bolt RAID, and that may not be worth the money.

Where's Ronnie? Is he working? Geez, always working...

Thank you Ben for your nice post

I'm assuming these are QT optimized files, right?

Yes they are.

I have looked deeper at my timeline, and it turns out it really happens with this project that uses Filmconvert.

So, basically, when the GPU is under heavy charge, MacOs becomes sluggy.

The irony is that the Mac Mini, who has no GPU, was working properly with the same project (and render was slower, of course)

Hey Ben,

Working on a major production right now, and at the same time preparing my presentation for a special FCP X event at IBC Amsterdam in two weeks. If anyone here is going to IBC, make sure to visit FCP Expo: sohoeditors.com/about-pages/fcp-expo-ibc...oho-editors-fcpworks

I will be at IBC from Friday 11th to Sunday evening 13th Sept. If anyone wants to have a drink with us, drop me an e-mail: ronnycourtens@mac.com

- Ronny

Arghh, I live in Amsterdam, and just when Ronny will make a presentation, I'm out of the country

Ronny I'm sure it will be a blast !!!

Manu,

I'm sure we will meet in Amsterdam one day soon.

As to your issue: Ben is correct (as always).

During rendering, FCP X constantly creates temp files on your system drive. Because this drive is nearly full it can become very slow, making it nearly impossible to do anything else on your machine while it's rendering your video. The GPU only takes away the load of your CPU. This results in a faster processing of your effects, but it does not make up for the slow speed of your system drive. And you need a fast and lean system drive to handle the OS and any opened applications. So you will have to make space on that drive if you want to process that kind of footage while still being able to do other things.

- Ronny

Thank you Ben and Ronny. Very clear, as usual.

Ben, Ronny

It's a bit more complex than I thought. When I mentionned 50Gb of free space, I had been to About... System...Storage

But I do right click on Macintish HD and info, I see 110Gb of free space.

It seems that the difference might be due to those "Backup files", files that Timemachine stores on the drive and deletes when there is no space.

I can't do much about this, can I ?

TimeMachine should be set to a dedicated, secondary (external) drive. Don't point it to a drive used for anything else. You want a minimum of 15% free space on any drive, especially the system drive.

Ronny, as soon as I find someone to pay my way, and watch my kids, I'll be at IBC! LOL

Hi Ben

It's not what I mean. Timemachine is of course on an secondary HDD.

Yet, OSX keeps some timemachine files on the internal HDD, and deletes them when there is a need of space. That is normal behaviour.

"These snapshots are designed to help you recover deleted files or previous versions of files, even if your laptop is away from its Time Machine drive for a while. Your Mac automatically creates them in the background, and the Time Machine icon on your menu bar won’t even say it’s doing anything as it does so. These local snapshots are stored on your Mac’s startup partition along with all your other files."

But I've just found an article on how to remove them

www.howtogeek.com/212207/how-to-free-up-...backups-on-your-mac/

So how much space were they taking up on your system drive?

53Gb !

Apparently it's only for laptops, not for desktops.

Conclusion, for those who use laptops. The tip is simply to purge Timemachine local snapshots when they get too big.

in terminal:
sudo tmutil disablelocal

wait a few minutes, and then:
sudo tmutil enablelocal

I've check three very well and often used laptops, none have gone over 40MB. 53GB is abnormally large, I think something isn't right.