36 lines
1.1 KiB
C
36 lines
1.1 KiB
C
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/**
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@file
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Implements cache replacement policies. Eventually, this could be
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extended to support application specific caching schemes.
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@todo Stasis used to use LRU-2S. LRU-2S is described in Markatos
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"On Caching Searching Engine Results". (This needs to be
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re-implemented properly.)
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For now, Stasis uses plain-old LRU. DB-MIN would be an interesting
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extension.
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If you would like to implement your own caching policy, implement
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the functions below. They are relatively straightforward. Note
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that replacementPolicy implementations do not perform any file I/O
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of their own.
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The implementation of this module does not need to be threadsafe.
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*/
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typedef struct replacementPolicy {
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struct replacementPolicy* (*init)();
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void (*deinit) (struct replacementPolicy* impl);
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void (*hit) (struct replacementPolicy* impl, int id);
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void*(*getStale)(struct replacementPolicy* impl);
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void*(*remove) (struct replacementPolicy* impl, int id);
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void (*insert) (struct replacementPolicy* impl, int id, void * page);
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void * impl;
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} replacementPolicy;
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replacementPolicy * lruInit();
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