Comments - TokuDB Differences

Here is a simple one liner to check the compression format of the TokuDB data files using the tokuftdump tool :

mysql -sNe 'SELECT dictionary_name, internal_file_name FROM information_schema.tokudb_file_map WHERE dictionary = "main" OR dictionary LIKE "key-%"' |perl -F'\t' -ane '@out=qx(tokuftdump --nodata --rootnode /var/lib/mysql/$F[1]); foreach $ftdump (@out) { if($ftdump=~/^ compression_method=([0-9]+)$/) { print $F[0]."\t".$1."\n"; last } }'

(don't forget to ajust to your datadir path if its not /var/lib/mysql)

The integer corresponds to the compression format, 0 is uncompressed, 8 is ZLIB and 10 is LZMA, the other format correspondances can be found on make_tdb.cc

On MariaDB5.5.37, the column "dictionary" has changed for "table_dictionary_name", so the right command is now :

mysql -sNe 'SELECT dictionary_name, internal_file_name FROM information_schema.tokudb_file_map WHERE table_dictionary_name = "main" OR table_dictionary_name LIKE "key-%"' |perl -F'\t' -ane '@out=qx(tokuftdump --nodata --rootnode /var/lib/mysql/$F[1]); foreach $ftdump (@out) { if($ftdump=~/^ compression_method=([0-9]+)$/) { print $F[0]."\t".$1."\n"; last } }'

Also note that the ZLIB compressed tables are having the value of 11 and not 8 as stated previously.

Hi, it does not work for me. Versions : tokudb_version - 5.6.26-74.0 , version mariaDB - 10.1.10-MariaDB-1jessie-log.

I've added --header to tokuftdump command. Finally it works for me :

 mysql -sNe 'SELECT dictionary_name, internal_file_name FROM information_schema.tokudb_file_map WHERE table_dictionary_name = "main" OR table_dictionary_name LIKE "key-%"' |perl -F'\t' -ane '@out=qx(tokuftdump --nodata --header --rootnode /var/lib/mysql/$F[1]); foreach $ftdump (@out) { if($ftdump=~/^ compression_method=([0-9]+)$/) { print $F[0]."\t".$1."\n"; last } }' 

And i noticed that changing compression method changes size of table on disk. But command

 SELECT 
    table_name AS `Table`, 
    round(((data_length) / 1024 / 1024), 2) `Table  size in MB` ,
    round(((index_length) / 1024 / 1024), 2) `Index  size in MB` 
FROM information_schema.TABLES 
WHERE table_schema = <table>
order by `Table  size in MB` desc; 

shows the same size of tables for different compression methods. Why ?