I wrote a page (cron.php) that uses the imap library to connect to a mailbox, parse messages, and store them in a database, then echos the results in json.  I have a few dozen mailboxes that I need to run this same process for, and so I put together a page (mailboxes.php) that lists all these accounts, each with a button that when clicked, essentially hits cron.php via AJAX and parses the json response to update the page when the process is completed.
I've noticed however that if I click each of these boxes, they return as if running serially, not in parallel. Is there a configuration option someplace that might explain this?
 
     
    