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@ -338,19 +338,19 @@ options.compression = leveldb::kNoCompression; |
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### Cache |
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### Cache |
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The contents of the database are stored in a set of files in the filesystem and |
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The contents of the database are stored in a set of files in the filesystem and |
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each file stores a sequence of compressed blocks. If options.cache is non-NULL, |
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it is used to cache frequently used uncompressed block contents. |
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each file stores a sequence of compressed blocks. If options.block_cache is |
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non-NULL, it is used to cache frequently used uncompressed block contents. |
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```c++ |
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```c++ |
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#include "leveldb/cache.h" |
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#include "leveldb/cache.h" |
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leveldb::Options options; |
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leveldb::Options options; |
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options.cache = leveldb::NewLRUCache(100 * 1048576); // 100MB cache |
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options.block_cache = leveldb::NewLRUCache(100 * 1048576); // 100MB cache |
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leveldb::DB* db; |
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leveldb::DB* db; |
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leveldb::DB::Open(options, name, &db); |
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leveldb::DB::Open(options, name, &db); |
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... use the db ... |
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... use the db ... |
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delete db |
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delete db |
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delete options.cache; |
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delete options.block_cache; |
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``` |
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``` |
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Note that the cache holds uncompressed data, and therefore it should be sized |
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Note that the cache holds uncompressed data, and therefore it should be sized |
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