how to use compression for titan?

[hiqsociety]

how to use compression for titan? i saw the delta compression, is there a configuration setting to enable it?

[tabokie]

titan/include/titan/options.h

Line 85 in 66a7a24

CompressionType blob_file_compression{kNoCompression};

The compression type is defined here:
https://github.com/facebook/rocksdb/blob/79f08d7ffa6d34d9ca3357777bcb335884a56cfb/include/rocksdb/compression_type.h#L17

[hiqsociety]

how do i do this configuration in tidb?

why then it's mentioned as a new feature on May?
#245

[tabokie]

https://github.com/tikv/tikv/blob/47d8c9e483db762cefe8725abac9f5110e97ae63/etc/config-template.toml#L873

"Delta compression" is a feature request (which is far from production-ready and we don't have the resources to accept it yet), compression in general is supported long ago.

[vipsland]

ok thx. everything make sense now.

looking forward to delta compression... seems like a great storage savings but not sure how much cpu time it takes

[cscetbon]

@tabokie did someone look into that feature proposal though ?

[tabokie]

@cscetbon Unfortunately no. We don't have the bandwidth and this is a very low-priority feature in the scope of TiKV. (An intern implemented zstd dictionary compression years ago and we haven't gotten around to test it in TiKV...)