25 lines
630 B
Markdown
25 lines
630 B
Markdown
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System Design
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Client -> TTL Cache -> Database
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Capacity C
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TTL increases on cache hit
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Age of information / Age of the entry in the cache
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Database has latest object, cache entry may be old (we don't know)
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Age of entry should have low age of information
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Update function from cache to refresh based on mu (refresh rate)
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Loss function based on TTL and age in cache called beta(i)
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Event based simulation
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lambda(i) is zipf distribution describing the rate the client requests the object "i"
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Inter arrival time of each object => exponential
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We need
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Hit rate and the average age of the object based on TTL and
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C = n (example: 100)
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