Yes, the metadata will be created if we create a folder in HDFS. Whenever any change occurs to the HDFS file system, it maintains the 2 types of files in its meta-data directory namely fsimage and an edit file.
1) FsImage – An fsimage file contains the complete state of the file system at a point in time. Every file system modification is assigned a unique, monotonically increasing transaction ID. A fsimage file represents the file system state after all modifications up to a specific transaction ID.
2) Edits – An edits file is a log that lists each file system change (file creation, deletion or modification) that was made after the most recent fsimage.
It will approximately take around 2 MB of memory for above 2 types of files.