wpmu_create_blog is very slow

When calling wpmu_create_blog in 4.2.4 it took less than a second to complete. In 4.4.2 it takes around 4-8 seconds to complete. I have to run batches of this from time-to-time and this is a substantial change in the amount of time it takes.

I would appreciate any help in getting this to run in a more reasonable amount of time.