title: A few question about PHP memcache
body: <p><strong>1)</strong><br>
  I understand I can call this</p>
  
  <pre><code>$memcache_obj = memcache_connect('memcache_host', 11211);
  </code></pre>
  
  <p>in the header files of my site with no impact on pages that don't use memcache
  but what about this</p>
  
  <pre><code>$memcache-&gt;connect('127.0.0.1', 11211);
  </code></pre>
  
  <p>Should this be called on a page to page basis?</p>
  
  <hr>
  
  <p><strong>2)</strong><br>
  what if the server does not have enough memory to write new caches and memcache tries to store a cache?</p>
  
  <hr>
  
  <p><strong>3)</strong><br>
  I know keys can have up to a 30 day lifespan,
  Is there a way to flush all keys out of memory, especially useful for testing phase?</p>
  
  <p><strong>4)</strong><br>
  Also this code, the first variable is connecting, so for example if I have 5 sections on a page that add/update/delete from memcache, do I need to run this connection everytime, or is it possible to connect 1 time and do everything per page load?</p>
  
  <pre><code>memcache_set($memcache_obj, 'var_key', 'some variable', 0, 30)
  </code></pre>
  
  <p><strong>5)</strong> 
  Is there a function or anything to show like how much memory is available and being used on a php page?</p>