@Override
  public DiskStoreFactory setMaxOplogSize(long maxOplogSize) {
    checkMinAndMaxOplogSize(maxOplogSize);
    attrs.maxOplogSizeInBytes = maxOplogSize * (1024 * 1024);
    return this;
  }
Checks if directories exist, if they don't then create those directories
geode-core/src/main/java/org/apache/geode/internal/cache/DiskStoreFactoryImpl.java