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What is mdworker on Mac Activity Monitor

Ever since I upgraded from 10.7 to 10.8 my iMac has its dual cores loaded >50% with mdworker. At times it causes the computer to run extremely slowly. How do I limit mdworkers time for indexing to my low usage times? Should mdworker run continuously?

[Re-Titled by Host]

iMac (24-inch Early 2009), OS X Mountain Lion (10.8)

Posted on Sep 19, 2012 4:26 PM

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7 replies

Sep 19, 2012 5:08 PM in response to n3rs

mdworker shouldn't work continuously, but it's a busy utility and very difficult to throttle. How much of the time is mdworker going? Another user made a great list of things to do in this case:



How much free drive space on the Mac?


Right or control click the MacintoshHD icon. Click Get Info. In the Get Info window you will see Capacity and Available. Make sure there's a minimum of 15% free disk space.


You can stop Spotlight from indexing > Spotlight tips


Have you emptied the Safari cache lately? From your Safari menu bar click Safari > Empty Cache. Quit then relaunch Safari to test.


If that didn't help, back to the menu bar, click Safari > Reset Safari. Select the top 5 boxes, click Reset. Try Safari.


And try troubleshooting the Safari .plist file (preferences)


Go to ~/Library/Preferences


Move the com.apple.Safari.plist file from the Preferences folder to the Desktop.


Quit, relaunch Safari to test.


If that helped, move the .plist file to the Trash, If not, just move it back to the Preferences folder.


And try troubleshooting Safari third party plugins. Go to Safari > Preferences then select the Security tab. Deslect: Enable plug-ins


Quit then relaunch Safari to test. If that made a difference, then you need to find the plugin(s) causing the problem > Unsupported third-party add-ons may cause Safari to unexpectedly quit or have performance issues

Sep 19, 2012 6:19 PM in response to n3rs

Poikkeus, thanks for the reply. mdworker runs all of the time since I loaded Mountain Lion. My HD in the iMac has 438 GB space available and 201 GB used. I rarely use Safari and I have cleared my Firefox cache. I also have cleared reset the top five boxes under reset Safari. Still no change. mdworker is consistently using >90% of my CPU. I'll look into the plist next.


Thanks!

Sep 19, 2012 9:50 PM in response to n3rs

Thanks for the extra data; that weeds out a few possible suspects.


First, the hardcore solution. mdworker is associated with Spotlight, and you can disable Spotlight using this procedure.

http://osxdaily.com/2007/03/22/how-to-completely-disable-spotlight/


Second, this activity is frequently associated with cloud backup, or an application like Backblaze. Disable cloud activity for a while to see if this is a factor.


Third, Time Machine is an application that's "always on" for some users. I use Time Machine for only twenty minutes a day, or when I need to backup. This might be the case for you.


Post and tell me if this worked for you.

Nov 20, 2015 3:13 AM in response to Poikkeus

Hello again and many thanks for your great answers. The problem is, that i don´t find the plist exactly with the name you described, see attached list:

file:///Library/Preferences/com.adobe.acc.AdobeCreativeCloud.plist

file:///Library/Preferences/com.adobe.acc.AdobeDesktopService.plist

file:///Library/Preferences/com.adobe.acrobat.pdfviewer.plist

file:///Library/Preferences/com.adobe.headlights.apip.plist

file:///Library/Preferences/com.adobe.reader.DC.WebResource.plist

file:///Library/Preferences/com.apple.airport.opproam.plist

file:///Library/Preferences/com.apple.alf.plist

file:///Library/Preferences/com.apple.alf.plist~orig

file:///Library/Preferences/com.apple.AppleFileServer.plist

file:///Library/Preferences/com.apple.applepushserviced.plist

file:///Library/Preferences/com.apple.AppleShareClient.plist

file:///Library/Preferences/com.apple.apsd.launchd

file:///Library/Preferences/com.apple.apsd.plist

file:///Library/Preferences/com.apple.BezelServices.plist

file:///Library/Preferences/com.apple.Bluetooth.plist

file:///Library/Preferences/com.apple.ByteRangeLocking.plist

file:///Library/Preferences/com.apple.captive.plist

file:///Library/Preferences/com.apple.CoreRAIDServer.cfdb

file:///Library/Preferences/com.apple.dockfixup.plist

file:///Library/Preferences/com.apple.driver.AppleIRController.plist

file:///Library/Preferences/com.apple.HIToolbox.plist

file:///Library/Preferences/com.apple.iLife.plist

file:///Library/Preferences/com.apple.iokit.AmbientLightSensor.plist

file:///Library/Preferences/com.apple.iPod.plist

file:///Library/Preferences/com.apple.loginwindow.plist

file:///Library/Preferences/com.apple.MCX.plist

file:///Library/Preferences/com.apple.noticeboard.plist

file:///Library/Preferences/com.apple.P2PSupervisor.plist

file:///Library/Preferences/com.apple.pcast_integration.plist

file:///Library/Preferences/com.apple.preferences.sharing.plist

file:///Library/Preferences/com.apple.print.makequeues.plist

file:///Library/Preferences/com.apple.screensaver.plist

file:///Library/Preferences/com.apple.security.appsandbox.plist

file:///Library/Preferences/com.apple.security.plist

file:///Library/Preferences/com.apple.security.systemidentities.plist

file:///Library/Preferences/com.apple.SetupAssistant.plist

file:///Library/Preferences/com.apple.SoftwareUpdate.plist

file:///Library/Preferences/com.apple.storeagent.plist

file:///Library/Preferences/com.apple.TimeMachine.plist

file:///Library/Preferences/com.apple.updatesetings.plist

file:///Library/Preferences/com.apple.windowserver.plist

file:///Library/Preferences/com.apple.xsanmgrd.plist

file:///Library/Preferences/com.epson.Document%20Capture.UnInstallList.plist

file:///Library/Preferences/com.epson.Epson%20Event%20Manager.UnInstallList.plis t

file:///Library/Preferences/com.epson.EPSON%20Scan.UnInstallList.plist

file:///Library/Preferences/com.microsoft.office.licensing.plist

file:///Library/Preferences/com.microsoft.PlayReady.plist

file:///Library/Preferences/com.skype.skype.plist

What is mdworker on Mac Activity Monitor

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