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Mysterious background tasks in iMovie make program slow, unusable

Hi,


I am using iMovie 10.0 on OS X 10.9 Mavericks build 13A603. The computer is a "late 2012" type iMac (2.7 GHz i5, 8 GB RAM).


Even when I close all other tasks, iMovie runs so slowly as to be unusable. Specifically, it seems that every time I run iMovie, it starts some mysterious background tasks that don't show up anywhere (no progress bar, no messages) and slow down the computer to almost a standstill. This happens even when I'm running a very small project in iMovie. When I try to close the program, it asks me: "Are you sure you want to close iMovie library? Tasks that are currently in progress will not be completed."


Please help me get rid of these mystery tasks so that I can finally get my work done. Thanks...

iMac (21.5-inch, Late 2012), OS X Mavericks (10.9)

Posted on Nov 9, 2013 7:29 PM

Reply
19 replies

Jun 14, 2017 4:35 AM in response to lichtpausen

This is kind of happening to me?

I tried to download an iMovie, But it came up with a message saying Quitting background tasks. I can't restart or shut down my computer because the iMovie app won't close. I also have tried almost everything I an but it still won't work. I'm not very good at technology but I need the iMovie application for a school project that's due in a couple days. I haven't heard of anyone else having this problem so I don't know if there is a solution, but if anyone knows please let me know!

Dec 23, 2013 1:15 AM in response to lichtpausen

I'm having exactly the same issue. iMovie is taking all the CPU power making the entire system performing very slow. Im my case iMovie is rendering a movie in the background altough it was already properly rendered. The process resposible for this task seems to ProTranscoderTool_sb. I tryed to force quit it and got message in the notification center that the "Shared failed; The share operation "movie" has failed". I had to force quit the process 3 times because iMove tried to render the same clip again. It solved the performance problem for now. But I am wondering why is the same movie being shared all over again.


Dec 23, 2013 3:22 AM in response to Lu Ko

I found this at first. If you update a lot of projects from iMovie 9 to iMovie 10 is has to reconvert all the clips into the new intermediate codec using the ProTranscoderTool before they can be shared. Even worse, if you had shake stabililzation active in many clips it will automatically re-analyze each clip and this is a very CPU - intensive task. Its just a matter of letting it get on with it. I think background tasks only start operating on the currently active project but if you load a different one it will start up on that as well as continuing with the ongoing ones.


Unlike FCP 10.1 which can display what background tasks are running 1Movie 10 deos not have this capability - only the Activity Monitor app can show you.


Geoff.

Dec 23, 2013 3:33 AM in response to GeeD

My penny to this


TO GET IT TO WORK SLIGHTLY FASTER

• Minimum of 25Gb free space on Start-Up hard disk

• No other programs running in BackGround e.g. Energy-Saver

• Don’t let HD spin down or be turned off (in Energy-Save)

• Move hard disks that are not to be used to Trash - To be disconnected/turned off

• Goto Spotlight and set the rest of them under Integrity (not to be scanned)

• Set screen-saver to a folder without any photo - then make an active corner (up right for me) and set pointer to this - turns on screen saver - to show that it has nothing to show

• No File Vault on - Important

• NO - TimeMachine - during iMovie/iDVD work either ! IMPORTANT

Lot's of icons on DeskTop/Finder also slows down the Mac noticeably

Start a new User-Account and log into this and iMovie get's faster too - if a project is in a hurry

• And let Mac run on Mains - not just on battery


Yours Bengt W

Feb 9, 2014 7:44 PM in response to Bengt Wärleby

Thanks for these small fixes. Yes, I'm having the exact same problems. This issue actually caused my macbook air to crash. I thought 10GB free on my hard drive was enough to do some editing. I did a bunch of dumb things at onces, like having Time Machine running, having a portable drive connected with other libraries. Having a couple other programs open didn't help either. Since then, I freed up 60 GB on my hard drive and it's still having the same issues. If I let iMovie run a while, it will use around 40GB of virtual memory. Now I keep Activity Monitor open and just close and re-open iMovie occasionally. It's barely useable. I'm not using stabilization on any clips again until the very end of editing. Apple better get on this if they want people to use the program.

Aug 18, 2014 8:08 AM in response to lichtpausen

I've run into this problem as well. Uncheck the "add to theater" box when sharing a file and in iMove preferences, uncheck "automatically upload content to iCloud". This supposedly only happens when items are added to the theater, but I wouldn't be surprised if something is going on anyway. I also went ahead and removed old projects so that I only have a few videos in the library. I have 23GB free on a 2013, Haswell Macbook Air, i7, 8gb.

Sep 13, 2014 12:37 AM in response to NickRedwoodCity

Reg Conspiratory Theory !


May be it is a strategy to force You to buy a new Mac.


To rule this out - DO


- Secure lot's of free Space on Start-Up Macintosh HD (25Gb or much more)

- Create a New User Account

- Log into this


Now try and see if Your Mac got into better pace - If not - Do as I - keep the old one with OS X.6 and don't up-date till it fall's into pieces. 😉


Yours (open for realistic and mysterious ways to keep it up and running) Bengt W

Dec 17, 2014 9:23 AM in response to lichtpausen

I found that when I have a lot of old events in my library, iMovie is very slow, as if it is opening all those events in the background in case I want to use clips from them. When I moved all those events into a separate library, and then closed that separate library, iMovie seems to run like new again. (Of course, since I did that last, I've added 71 new events to my library, and iMovie has slowed to a crawl again...so the number of events does seem to be related)

Mysterious background tasks in iMovie make program slow, unusable

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