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The "StorageConfiguration" page has been changed by JonHermes.
http://wiki.apache.org/cassandra/StorageConfiguration?action=diff&rev1=54&rev2=55

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   * '''memtable_flush_after_mins''', '''memtable_operations_in_millions''', 
and '''memtable_throughput_in_mb'''
  
- '''memtable_flush_after_mins: '''The maximum time to leave a dirty memtable 
unflushed. (While any affected columnfamilies have unflushed data from a commit 
log segment, that segment cannot be deleted.) This needs to be large enough 
that it won't cause a flush storm of all your memtables flushing at once 
because none has hit the size or count thresholds yet.  For production, a 
larger value such as 1440 is recommended.
+ memtable_flush_after_mins: The maximum time to leave a dirty memtable 
unflushed. (While any affected columnfamilies have unflushed data from a commit 
log segment, that segment cannot be deleted.) This needs to be large enough 
that it won't cause a flush storm of all your memtables flushing at once 
because none has hit the size or count thresholds yet.  For production, a 
larger value such as 1440 is recommended.
  
- '''memtable_operations_in_millions: '''The maximum number of columns in 
millions to store in memory per ColumnFamily before flushing to disk.  This is 
also a per-memtable setting.  Use with {{{MemtableSizeInMB}}} to tune memory 
usage.
+ memtable_operations_in_millions: The maximum number of columns in millions to 
store in memory per ColumnFamily before flushing to disk.  This is also a 
per-memtable setting.  Use with {{{MemtableSizeInMB}}} to tune memory usage.
  
- '''memtable_throughput_in_mb: '''The maximum amount of data to store in 
memory per !ColumnFamily before flushing to disk.  Note: There is one memtable 
per column family, and  this threshold is based solely on the amount of data 
stored, not actual heap memory usage (there is some overhead in indexing the 
columns). See also MemtableThresholds.
+ memtable_throughput_in_mb: The maximum amount of data to store in memory per 
!ColumnFamily before flushing to disk.  Note: There is one memtable per column 
family, and  this threshold is based solely on the amount of data stored, not 
actual heap memory usage (there is some overhead in indexing the columns). See 
also MemtableThresholds.
  
+ Both mem_ops and mem_size are defaulted based on the heap allocation during 
boot.
+ 
- Defaults are: '60' minutes, '0.3' millions, and '64' mb respectively.
+ Defaults are: '60' minutes, 'HeapSize/2**29 * 0.3' millions, and 
'HeapSize/2**23' mb respectively.
  
   * '''partitioner'''
  

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