Finder not working after update to 10.10.3

Question

I have updated to the latest version 10.10.3 of Yosemite and any task involving the finder now takes several minutes, making my Mac useless. I have plenty of RAM (12GB). I have tried the following:
- Deleted and let the system rebuilt CloudKitMetadata, CloudKitMetadata-shm, CloudKitMetadata-wal and com.apple.finder.plist
- remove some cache:
com.apple.finder
CloudKit > com.apple.finder
CloudKit > com.apple.clouddocs
CloudKit > com.apple.CloudDocs.container-metadata
CloudKit > CloudKitMetadata
CloudKit > CloudKitMetadata-shm
CloudKit > CloudKitMetadata-wal
com.apple.icloud.fmfd
com.apple.iCloudHelper
This has changed nothing.
Thanks to anybody for suggestion.

Answer 1

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad and start typing the name.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen.
Click the Clear Display icon in the toolbar. Then take an action that isn't working the way you expect. Select any lines that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
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