How a crawler decides what to fetch next
13 August 2026 · Crawling
A crawler is a queue with a fetcher attached to it. Everything that feels mysterious about being crawled becomes ordinary once you picture the queue: a long list of addresses waiting their turn, reordered constantly, and trimmed whenever it grows faster than the machines can drain it.
Your page being known and your page being fetched are two separate events, and the gap between them can be months.
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