does postgresql backup require additional space on disk

[Julie Nishimura <juliezain@xxxxxxxxxxx>]

Hello,

we are almost out of disk space on one of our servers (99% full). If we run pg_dump to a diff location, does it require any additional disk space on our current server? I am asking, because on some other software, a backup might open transaction which keeps growing and eventually consume all space, keeping tran open for the backup duration. Please clarify? Thanks