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Settings are changed by:

(settings "key" "value")

And read by:

(settings "key")

The following settings are available:

  • "Backtrace": true or false whether to print backtraces from Scheme. Using true decreases the performance by ~10% but gives you better debugging capabilities.
  • "PartitionMaxDimensions": number from 0 to 10 how many partitioning dimensions are allowed at max. 0 means, don't partition shards for values (use it to workaround bugs), 1 means only one-dimensional partitioning.
  • "DefaultEngine": one of "memory" "sloppy" "logging" "safe" that defines which persistency level to choose if a CREATE TABLE statement is executed without the ENGINE parameter
  • "ShardSize": default 60000, defines the size of a shard. Rule of thumb is that no shard scan should last longer than 100ms. For servers and workstations, a shard size of 60,000 is recommended. On Raspberry Pi, you should tend to 10,000 in order to get good use of parallelism.