oramon contains just one executable binary, no installation is required, just download and extract it. Usually we run this utility on database server side, so it can get the database server's OS load information, which can help you analyze the performance problem. On Windows platform, you can write a batch script to start it as following.
@echo off
oramon -koramon.key
On Linux/UNIX, please set the environment variable LD_LIBRARY_PATH to Oracle's 32 bit client library path, as following.
#!/bin/csh
setenv ORACLE_SID sid
setenv ORACLE_HOME path
setenv ORACLE_PATH $ORACLE_HOME/lib32
./oramon_linux_10204.bin -koramon.key &
Then oramon will keep running, keep gathering the performance data and writing them to few text files. No worry about the disk space of the output files, if the main file exceed 50MB, it will do a rotation, the total disk space requirement is about 700MB. If you gather performance data at 10 seconds interval, it can keep about 3 months history data, if you gather data at 30 seconds interval, it can keep about 9 months history data.
ANYSQL_OMON.log (current)
ANYSQL_OMON.1.log (old file)
ANYSQL_OMON.2.log (older file)
When you hit performance issue, just analyze the history performance data, and find out the root cause.