It turns out that the Amazon product advertising API only allows 2000 API calls per hour.
Each call returns 10 products, so every hour I can call 20,000 products.
I used the product_search call to make calls for each category, per page, retrieving 20,000 products per hour. Over the course of several days, I have accumulated more than 1 million products.
Anyone who is interested in how this is done, let me know!
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