Compress rocksdb database with uncompressed files

[ashwin konale]

Hi all,

We have a service which uses rocksdb. (6.3.6) . I am trying to upgrade this to latest version. We have lots of uncompressed data (~500G). I would like to compress this using snappy. How do I go about it ? These are the things I have tried (in java)

1. Set CompressionType.SNAPPY and force compaction. But sst_dump shows that no compression algorithm is selected (N/A). 
2. Use sst_dump --command=recompress. In this case I get 'Unsupported compression type: kSnappyCompression'. Snappy and snappy-devel is installed in centos machines I have.
3. Use ldb compact command. This gives me 'Compression type Snappy is not linked with the binary.' error. 

Any help would be much appreciated.