在压缩文件中压缩记录的好算法是什么？

Suppose you have a large file made up of a bunch of fixed size blocks. Each of these blocks contains some number of variable sized records. Each record must fit completely within a single block and then such records by definition are never larger than a full block. Over time, records are added to and deleted from these blocks as records come and go from this "database".Suppose you have a large file made up of a bunc