I have CiviCRM 4.6.28 on Drupal 7.56, hosted on Pantheon.
We are trying to import lists of contacts, but anything above 250 contacts throws a timeout error, due to Pantheon's time limits. The time limit is 240 seconds, and the files vary between 14 and 30 kbs.
I've traced the resource usage back to find that the issue is that Smarty is being used during the import. Pantheon is showing Smarty as using a lot of resources, and I believe this is the issue because we can import event participants without problem, and the only difference in resource usage seems to be that event participant imports don't use Smarty.
So, now I am trying to figure out how to get it to stop using Smarty during import. I am thinking that it is using it for handling the email greetings field. Is there a way to turn off this field? We do not have special e-mail greetings for users.