<rant>I wish I never upgraded to OS X 10.9, it is so buggy!! But the alternative to stick with the unpatched earlier version of OS X was not a solution!
Anyway, so I am on this crappy Mavericks and since I have either full OS freeze or some other weirdness, slowness.
Today's one is "simple": the finder freezes while browsing the local SDD too often!
I open finder, go under Documents (on my local SSD) it contains only 31 items, 5 PDF wiht size 10-50MB, 1 PDF fo 300MB, the rest are small TXT, ODS, XLS, HTML of < 1MB and 5 subfolders. While scrolling through the view, it freezes, sometimes the display in the finder windows is all white, sometimes the beach ball is turning, sometimes you wait just a couple of seconds, some other times it is closer to 20 sec.
Documents is one example, but it is not limited to that folder sadly. Even the home folder which contains 15 subfolder and 3 files (for a total of 500kB!!) has such lock-up.
There is close to no activity on the machine, but when browsing the finder and when it locks, 1 to 2 processes are often quite active: Finder itself (always) and QuickLookSatellite (sometimes). Memory or disk IO/transfer do not show any spikes and are rather low in usage anyway. So there is no apparent reason for this behaviour than Mavericks quality...
Note: I have tried this tips regarding Finder slowness, but in my case it did not help.
Edit 01: I have removed all tags, but this did not help. However, I have found out that I have the problem in some of the Finder's view, so in the "icon" view it freezes for no reason but not in the "list" view for example.