It's normal for Cassandra to use more disk space than MySQL. It's part of what we trade for not having to rewrite every row when you add a new column.
"SSTables that are obsoleted by a compaction are deleted asynchronously when the JVM performs a GC." http://wiki.apache.org/cassandra/MemtableSSTable On Wed, Jan 5, 2011 at 8:35 AM, nicolas lattuada <nicolaslattu...@hotmail.fr> wrote: > Hi > > i have some data size issues: > > i am storing super columns with the following content: > > {a=>1, b=>2, c=>3.......n=>14} > > i am storing it 300 000 times and i have a data size on the disk about 283Mo > > And in other side i have a mysql table which stores a bunch of data the > schema follows: > 6 varchars +100 > 5 ints +6 > > I put about 1 300 000 records on it and end up with 150Mo of data and 57Mo > of index. > > Then i think i am certainly doing something wrong... > > The other thing is when i run flush and then compact the size of my data > increases, then i imagine something is copied up on compaction > So is there a way to remove the unused data? (cleanup doesn t seem to do the > job). > > Any help to reduce the size of the data would be greatly apreciated! > Greetings > > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
