Revise · W08 · Day 6Counting at Scale: Bloom Filters, HyperLogLog, Count-Min Sketch and Top-K
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Key ideaDay 6 · 1/10
Counting means remembering
Exact distinct counts cost memory per distinct key, per slice, per day: 10M visitors in 3 of 10,000 cells is ~1.2GB a day. Sketches cost a fixed amount with a known, bounded error.
← → flip · space next / show answer · S shuffle · esc exit1 / 10