Dropbox - echo 100000 | sudo tee /proc/sys/fs/inotify/max_user_watches

Dropbox comes up with the error message:

echo 100000 | sudo tee /proc/sys/fs/inotify/max_user_watches

Unfortunately anything put in /proc/sys is not permanent and your back at square one on next boot. There are a couple of fixes it for the issue though.
1) Edit /etc/sysctl.conf and add the following:

# Fix for Dropbox
fs.inotify.max_user_watches=100000

2) Edit /etc/rc.local and add the following:

echo 100000 | tee /proc/sys/fs/inotify/max_user_watches

Any one will permanently fix the error (as far as I understand) I am using method 1.

This is a brief explanation of the issue that I found at http://forums.dropbox.com/topic.php?id=29130

This is from the "advanced" section of https://www.dropbox.com/help/145:
"Monitoring more than 10000 folders
The Linux version of the Dropbox desktop application is limited from monitoring more than 10000 folders by default. Anything over that is not watched and, therefore, ignored when syncing. There's an easy fix for this. Open a terminal and enter the following:

sudo sysctl fs.inotify.max_user_watches=100000 

This command will tell your system to watch up to 100000 folders. Once the command is entered and you enter your password, Dropbox will immediately resume syncing."

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render vs redirect_to in Ruby on Rails

Here's what you need to know when you're deciding between a render and a redirect_to in your controller action

render
This will render a particular view using the instance variables available in the action.
For example if a render was used for the new action, when a user goes to /new, the new action in the controller is called, instance variables are created and then passed to the new view. Rails creates the html for that view and returns it back to the user's browser. This is what you would consider a normal page load.

redirect_to
This will send a redirect to the user's browser telling it to re-request a new URL as 302 redirect response. Then the browser will send a new request to that URL and it will go through the action for that URL, oblivious to the fact that it was redirected to. None of the variables created in the action that caused the redirect will be available to the redirected view. This is what happens when you click on 'Create' in a form and the object is created and you're redirected to the edit view for that object.

If you do not have a render or a redirect_to in your controller method for a particular action then Rails will automatically render the template for that action. For example if your action is new, rails will render the view for new: new.html.erb.

If you need to render another action's view, you can use render :action_name.

If you need the user to run a new action, use redirect_to :action => :action_name. For example if the user has clicked 'Create' and there are no errors in creating the object, you can use redirect_to :action => :show to show the successfully created object.

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render vs redirect_to in Ruby on Rails

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Related posts:
Difference between update_attribute and update_column 
What is different in update_all, update,  update_attribute, update_attributes methods of Active Record
Difference between .nil?, .empty?, .blank?, .present? 
render vs redirect_to in Ruby on Rails

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