Re: [infinispan-dev] SimpleFileCacheStore

On 31 Jul 2013, at 08:22, Radim Vansa <rvansa(a)redhat.com&gt; wrote: >>> >>> I noticed that is neither a log structured nor a b/b+ tree implementation and it lacks compaction. Maybe it is elsewhere or I simply missed it? > > No, the storage does not need any search structure as it keeps all keys > with entry position in-memory, what is its major drawback. And also one of its major benefits. Reading an entry off disk is very quick, since the entry position is in memory. Think of it as a DB index. LevelDB also has a concept of holding entry positions in an index, only that it keeps the position index in memory up to a predefined size, after which it persists the position index to disk. That may mean two disk reads for a single entry, but still proves to be fairly efficient.