How to load a large amount of users
I was running into this issue as well. I ended up using EntityFieldQuery to pull my nodes. Then also went into my php.ini file and set my resource limit params to what I have pasted below.

max_execution_time = 1024     ; Maximum execution time of each script, in seconds
max_input_time = 2048   ; Maximum amount of time each script may spend parsing request data
memory_limit = 5048M      ; Maximum amount of memory a script may consume (8MB)


I've included my php module code below for your reference as well.

// go through player names and search
$query = new EntityFieldQuery();
$query-&gt;entityCondition('entity_type', 'node')
  -&gt;entityCondition('bundle', 'content_type_name_to_pull')
  -&gt;propertyOrderBy('title', 'ASC')
  -&gt;propertyCondition('status', 1);

$result = $query-&gt;execute();

if (!empty($result['node'])) {
  $nids = array_keys($result['node']);
  $nodes = node_load_multiple($nids);

  foreach ($nodes as $node) {
    // do what you want with the node
  }
}