quicklookd and revisiond eating my CPU

I'm observing regular and abnormal CPU usage on my macbook pro. quicklookd in par with revisiond are eating together over of 50%. It drains my battery significantly and makes the whole machine hot.

I'm not sure when exactly it started but I'm suspecting latest 10.10.3 upgrade as I didn't notice this before.

After reading some post on the net I cleared ~Libraries/Cache and /private/var/folders then rebooted. It looked like the problem was gone (those processes didn't show up), but only for a while. The next day I resumed from sleep, again - quicklookd and revisiond started to burn my CPU.

Any clues how to get rid of this? What's causing this problem? It looks like these two processes are somehow connected, because when I cleared the cache and restarted none of them used a lot of cpu. Today, both of them do (quicklookd 24-30% , revisiond ~15%).

[Update]

Running sudo opensnoop -n revisiond shows nothing.

Running sudo opensnoop -n quicklookd brings endless list of entries like these:

  UID    PID COMM          FD PATH                 
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /
  501   4783 quicklookd    21 /
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /                    
  501   4783 quicklookd    23 /

It goes on and on and on. It's just endless. FD column is always 23 except two or three 21.

[Update 2]

After few minutes I got some other entries besides 501 4783 quicklookd 23 / (not pasting theme here as they were irrelevant)

And then again, whole lot of 501 4967 quicklookd 23 /

[Update 3]

I've also noticed that diskarbitrationd and diskmanagementd scores quite high (~ 5%) and stay on top of the process list (sorted by CPU usage) just below quicklookd and revisiond. Looks like this also might have something to do with this issue.

I've closed (cmd + q all other apps to make sure nothing interferes the measurements).

[Update 4]

Found few interesting entries in console:

Failed to obtain sandbox extension for path=/Users/me/Library/Caches/com.apple.quicklook.satellite. Errno:1
CGSConnectionByID: 0 is not a valid connection ID.
[QL] Using too much memory (161 MB), hit critical threshold (120 MB), exiting immediately to clean up.
[QL] Unable to write memory cache on disk
In -[NSApplication(NSQuietSafeQuit) _updateCanQuitQuietlyAndSafely], _LSSetApplicationInformationItem(NSCanQuitQuietlyAndSafely) returned error -50

They repeat few regularly each day. Especially those about memory and invalid connection.

[Update 5]

sudo iosnoop -n quicklookd revealed this:

  UID   PID D    BLOCK   SIZE       COMM PATHNAME
  501  5656 W 56385320  32768 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 56385320   4096 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 48100696  12288 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100816   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100840   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 56385640  28672 quicklookd ??/T/etilqs_kYNR5XinU71bydh
  501  5656 W 56386736  32768 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 56386736   4096 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 48100696  12288 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100816   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100840   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 56387280  28672 quicklookd ??/T/etilqs_ejadCww3DunYuu3

cloudthumbnails.db and cloudthumbnails.db-journal repeats and repeats.


This is how I fixed this problem. It might help you but from what I've seen so far, even thought there are similar issues, the source of problems are different.

I've ran sudo iosnoop -n quicklookd - it shown something like this:

  UID   PID D    BLOCK   SIZE       COMM PATHNAME
  501  5656 W 56385320  32768 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 56385320   4096 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 48100696  12288 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100816   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100840   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 56385640  28672 quicklookd ??/T/etilqs_kYNR5XinU71bydh
  501  5656 W 56386736  32768 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 56386736   4096 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 48100696  12288 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100816   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100840   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 56387280  28672 quicklookd ??/T/etilqs_ejadCww3DunYuu3
  501  5656 W 56474504  32768 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 56474504   4096 quicklookd ??/Quick Look/cloudthumbnails.db-journal
  501  5656 W 48100696  12288 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100816   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 48100840   8192 quicklookd ??/Quick Look/cloudthumbnails.db
  501  5656 W 56474568  28672 quicklookd ??/T/etilqs_QzHS30kC4YT8ETi

I gave it a shot and looked for cloudthumbnails.db file. Bingo! Found it in /Users/me/Library/Application Support/Quick Look and the quicklookd was writing to cloudthumbnails.db-journal like crazy. But it was writing small chunks, then deleting the file and writing those small chunks again. Unfortunately this is a binary file, so it's not easy to read, but I gave it a shot and just did tail cloudthumbnails.db-journal. I got mostly gibberish, but I noticed repeated path /Users/me/Library/Mobile Documents/com~apple~CloudDocs/ and some files there.

This is iCloud folder and for some reason quicklookd was unable to process those files. I deleted them (moved to trash and emptied) and TADA! It solved the problem.

I have no idea why this happened, why quicklookd was unable to process those files. I've sent those files again to iCloud and everything was fine - no crazy behavior of quicklookd.


I would try using opensnoop to see what files quicklookd is looking at. There might be a particular files that it is either having trouble reading or writing to.

While they are using excessive CPU, open a Terminal window and type the following command. You'll be prompted for your password.

 sudo opensnoop -n quicklookd

This should show you all the files that quicklookd is reading or writing to, and might help you identify if one particular file or folder of files is causing the issue.

Try the same thing for revisiond.