On Sun, Sep 23, 2012 at 8:18 PM, ÷¦ÔÁÌ¦Ê ôÉÍÞÉÛÉÎ <firstname.lastname@example.org> wrote:512MB per sstable? šWow, that's freaking huge. šFrom my conversations
> If you think about space, use Leveled compaction! This won't only allow you
> to fill more space, but also will shrink you data much faster in case of
> updates. Size compaction can give you 3x-4x more space used than there are
> live data. Consider the following (our simplified) scenario:
> 1) The data is updated weekly
> 2) Each week a large SSTable is written (say, 300GB) after full update
> 3) In 3 weeks you will have 1.2TB of data in 3 large SSTables.
> 4) Only after 4th week they all will be compacted into one 300GB SSTable.
> Leveled compaction've tamed space for us. Note that you should set
> sstable_size_in_mb to reasonably high value (it is 512 for us with ~700GB
> per node) to prevent creating a lot of small files.
with various developers 5-10MB seems far more reasonable. š I guess it
really depends on your usage patterns, but that seems excessive to me-
especially as sstables are promoted.