The ×100 latency ladder

RAM ~100 ns, SSD ~100 µs, spinning disk ~10 ms — each rung roughly 100× slower.

Why it works

Six orders of magnitude between memory and disk is why caching dominates systems design. One disk seek costs ~100,000 RAM reads.

More in Computers

• 2¹⁰ ≈ 10³Every 10 bits multiplies by ~1,000 — kibi and kilo differ by just 2.4%.
• Each subnet bit halves the hostsEvery bit moved from host to network halves the addresses — a /24 has 254 usable.
• RAID is not a backupRAID protects against disk failure — deletion, ransomware and fat fingers replicate instantly.
• 3-2-1 backupsKeep 3 copies of anything that matters, on 2 different media, with 1 off-site.

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