please let me know how i extend TEMPSPACE.

i got error messege below,

ADM6017E The table space "TEMPSPACE1" (ID "1") is full. Detected on container
"/home/db2inst1/db2inst1/NODE0000/SQL00004/SQLT0001.0" (ID "0"). The
underlying file system is full or the maximum allowed space usage for the file
system has been reached. It is also possible that there are user limits in
place with respect to maximum file size and these limits have been reached.

i found that garbage increases in this space little by little by loading data every day.ii don't know why)
i can't delete garbage, so i want to extend TEMPSPACE.
but this space is sms, and internet help@says, setting up beforehand is

is it the only way that i reboot server to clean up space periodical
when TEMPSPACE is near the limit?

please help.