I will mail you, but here is what Dreamhost support sent me:
While it may be compatible, shared hosting has inherent limitations due to the resources being used. In this case, while it's not the process watcher daemon killing your processes, the PHP scripts themselves are timing out
That would be indicative of the script itself - the limits are as high as we can set them, I'm afraid. You can further increase the limits if you'd like in the phprc file here:
/home/website/.php/5.6/phprc
Unfortunately, as this is very specific to the script you are running, we are not able to directly assist I'm afraid.