Even 1 million page views per day is only 12 page view per second on average. Unless your website traffic is really peaky, I don't think you would get too much

Even 1 million page views per day is only 12 page view per second on average. Unless your website traffic is really peaky, I don't think you would get too much trouble using sqlite over real db server. And if you do have a problem, swapping db in django is really easy anyway. Most sites I manage usually only got ~10x increased traffic during their peak hour compared to their least busy hour.