If you after run sqlplus or tnsping on Oracle 9i program KILLED and write
"out of memory" your installarion Oracle 9i x86_46 is wrong.
You installed your server the same as 32 bit.
For example these is good solution for Installing Oracle 9i on Red Hat
Enterprise Linux 4 64-bit:
http://blog.habben.org/2007/03/installing-oracle-9i-on-red-hat.html