mds/mdworker process takes CPU usage over 90%

What is MDS in Mac OS?


mds stands for “metadata server” and the mds process is part of Spotlight, the amazingly powerful and very useful search feature built directly into the foundation of Mac OS X.

Is the mds process related to mdworker?


Yes. Usually you will see the mds process in conjunction with mdworker, which is another part of Spotlight and it’s indexing engine.




How long does mds & Spotlight take to finish indexing?


How long it takes to update the Spotlight index depends on a few variables, but mostly the size of your hard drive, the amount of data being indexed, major changes to the filesystem, and the time since last indexing. Just let the indexing complete, it generally takes between 15 and 45 minutes to complete.


When you Mac OSX is indexing, the icon will be different ( the magnifying glass will have a dot in the center )

Click the Icon, you will see the progress of indexing 

You could stop mds service as:

shell>sudo mdutil -a -i off

Re-enabling Spotlight

shell>sudo mdutil -a -i on 

Now Spotlight indexing will be back on and work as usual. 

Remarks:
when you installed Mac OSX in vmware , I sugguested you did as follow:
(1) closed Spotlight , if you have no enough resource
(2) closed any Screen Saver (no Screen saver)
(3) closed Energy Saver,
     System Preference -> Energy Saver -> Computer Sleep ( Never)
                                                               -> Display Sleep (Never)
     (unchecked) put the hard disk(s) to sleep when possible
     取消能源節約器相關設定（讓電腦進入睡眠，讓顯示器進入睡眠），並不讓硬碟進入休眠

reference:
http://osxdaily.com/2010/08/05/mds-mac/
http://mac.pcbeta.com/viewthread.php?tid=65117