message: Flatten db-diskdown directory levels
diff: @@ -20,6 +20,7 @@ type FilePath = {
  };
  const LRU_SIZE = 8192;
  +const DIR_DEPTH = 1;
  const l = logger('db-diskdown');
  const noop = () =>
  @@ -47,10 +48,10 @@ class DiskDown extends AbstractLevelDOWN {
  // NOTE We want to limit the number of entries in any specific directory. Split the
  // key into parts and use this to construct the path and the actual filename. We want
  // to limit the entries per directory, but at the same time minimize the number of
  - // directories we need to create (when non-existent)
  - const parts = this.__keyToString(key).match(/.{1,2}/g) || [];
  - const directoryPath = `${this.location}/${parts.slice(0, 3).join('/')}`;
  - const filePath = `${directoryPath}/${parts.slice(3).join('')}`;
  + // directories we need to create (when non-existent as well as the size overhead)
  + const parts = this.__keyToString(key).match(/.{1,3}/g) || [];
  + const directoryPath = `${this.location}/${parts.slice(0, DIR_DEPTH).join('/')}`;
  + const filePath = `${directoryPath}/${parts.slice(DIR_DEPTH).join('')}`;
  let directoryExists = false;
  let fileExists = true;
  