How to free inodes in Linux without killing processes

One of databases (10.2.0.4) is filling up it's bdump, cdump and udump directories, deleting the files does not free any space because the inode is still being hold by many processes.

One way to free the space is killing the processes however pmon, smon are holidng the files so killing them instance will sink. I wonder if there is any better way to handle this? Or any way to prevent this happening (for example instead of deleting echo /dev/null to the file? my experience with this is that it does not work)

This is Linux x86-64

Alex

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