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Update 系统设计基础.md

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补充秒杀系统的设计：层层过滤请求、Redis Lua 预扣库存、异步下单和数据库兜底；补充海量数据处理：Top K、按哈希切分、位图和外部排序，并配图。
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CyC2018
2026-10-26 01:17:35 +08:00
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commit 3687d5ee19
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tools/diagram/src/massive-topk.svg
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<text x="360" y="28" class="title">100 GB 日志中出现次数最多的 10 个 URL（内存 4 GB）</text>
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tools/diagram/src/seckill.svg
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