postgresql – The size of the pg_xlog_archive folder is very large

During PostgreSQL database operations, pg_xlog_archive consumes more than 150 GB of disk space with the option "archive_mode = on". How to clean / reduce the size of the pg_xlog_archive folder.

What will happen if I disable "archive_mode = off". I've tried the "off" option too but the database operations take too much time. How does archive_mode work?