title: What level does mongodb write lock take place?
body: <p>I am beginning to research technology for a project, that can have frequent large writes.  I am wondering at what level does mongo write lock take place?  Is it at the server level or database level?  I have read <a href="http://www.mongodb.org/display/DOCS/How+does+concurrency+work" rel="nofollow">http://www.mongodb.org/display/DOCS/How+does+concurrency+work</a> but official documentation says. <code>a write operation can block all other operations.</code></p>
  
  <p>To me this means write locks are server level but I am hoping they are db level.  Could someone please confirm or deny this?</p>