The idea is to user your RAM in order to put there the temporary tablespace ( I suppose you have a box with a lot of GB for RAM ).
Sometimes , your database could have a bottleneck in your temporary tablespace ( in case of large sorts ) .
RAMFS is a good filesystem which resides in your RAM memory. This means that the data in RAMFS get lost forever when there is a electrical problem and your server is restarted or stopped .
This is not such a big problem in our case, because in OracleDB, temporary tablespace does not contain persistent information and is not subject to the recovery mechanism .
Read and write in your ramfs filesystem will be very fast.
In case your server is restarted, we can switch to the old temporary tablespace ( alter database default temporary tablespace temp; )
mount -t ramfs -o size=500m ramfs /ramfs
In your oracle database ( as user sys or system ) :create temporary tablespace temp_ramfs tempfile '/ramfs/temp_ramfs.dbf' size 10M autoextend on next 10M maxsize 32G; alter database default temporary tablespace temp_volatil ;