URLs waiting to be visited. Web page queues within hosts are largely dictated by "URL scheduling". Queues can be managed through various sorting processes based largely on the frequency of changes and the importance of pages. In a migration, probably after Googlebot has notified the various actors in the search engine crawling system (URL scheduler, history logs, etc.), the URLs to be crawled will be sorted and queued. expectation depending on what is known of the URLs from which it is redirected. If you
have a lot of "unimportant URLs", or pages with non-critical historical changes, or pages that change, but the features they contain are not important enough fax number list to constitute a "material change", you you may have to wait a while in the queue. after the migrations. And that before any “host load” issues. The schedule still applies during migrations, but your queue of URLs to crawl has grown When I asked John Mueller if scheduling still applied during migrations (August 2016), he said yes, continuing:
We can't suddenly crawl a brand new huge full website after a migration. Exploration efficiency is always essential. During a site migration, you've effectively added an extra copy full of your site's worth crawling URLs. This is even worse if you decided to merge multiple individual sites at a new folder level into an existing main site to consolidate - even more URLs. Suddenly you're asking Googlebot to crawl double the number of