cfprefsd writes to disk like crazy

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Level 1

5 points

cfprefsd writes to disk like crazy

hi all,

do you have this process, too? There is a process called cfprefsd that writes large amounts of data to hard disk, it writes 3.4GB to disk only 30 minutes after a reboot. It's a Yosemite freshly installed a few days ago.

Also weird is, the free space of disk keeps fluctuating up and down by a few hundred MBs, so the process does not write that much to disk as the activity monitor shows.

A search with Google says the process is a valid part of OS X, but I am still worried about being hacked or something...Could you verify if your machine also have this problem? Thank you!

best regards,

-Rick

MacBook Pro with Retina display, OS X Yosemite (10.10)

Posted on Oct 23, 2014 8:54 PM

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Answer 1

empter

Level 1

10 points

Oct 28, 2014 12:15 AM in response to iphone7166

my cfprefsd is crazy too.it writes 16.5G in two days

and after reboot,it writes about 1G/hour

my Yosemite is upgrade from 10.9.5

seems 10.9 didn't have this problem

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Answer 2

empter

Level 1

10 points

Oct 28, 2014 8:28 AM in response to iphone7166

use fs_usage to trace cfprefsd i found it has large operations with com.apple.Safari.Extensions.plist,so i delete all Extensions.

seems solved after uninstall adblock plus,then i install adblock instead of plus,cfprefsd stops writing!

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Answer 3

iphone7166 Author

Level 1

5 points

Oct 28, 2014 6:43 PM in response to empter

Wow, thank you, empter! It is adblock plus indeed, and you taught me another tool 🙂

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Answer 4

Dec 7, 2015 4:07 AM in response to empter

For me it was Bluetooth preferences that were being written. I turned off bluetooth and it "fixed" it.

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Answer 5

Feb 1, 2016 8:13 PM in response to AshCoolman

I'd just like to bump this in the slim chance that Apple sees it. I've had my MacBook overheating like crazy and slowing to a crawl. All I had paired to it was a bluetooth keyboard. I disabled bluetooth and, as AshCoolman put it, that "fixed" it. This needs a more permanent fix.

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Answer 6

May 20, 2016 1:47 PM in response to Anthropogenesis

Using bluetooth keyboard and mouse.

For me, 834GB - Gigabytes!!!! Almost a terabyte! Insane.

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