> a categorization of the background processes, plus which ones are > started by default, which ones are required Speaking of "which ones [background processes] are required", if you use Oracle 10g or up on Linux/UNIX, there's an easier way to check: --- begin quote --- Beginning with 10g, Oracle background processes on Linux/UNIX have an environment variable SKGP_HIDDEN_ARGS. On Linux, the variable is assigned a value and its first attribute can tell you whether killing this process would crash the instance: $ ps eww $(pgrep -f ora_pmon_$ORACLE_SID) | perl -nle 'print $& if /SKGP_HIDDEN_ARGS=[^ ]+/' SKGP_HIDDEN_ARGS=<FATAL/S/x0/x1/x0/x3E5839D4/6015/6015/x0> $ ps eww $(pgrep -f ora_mmon_$ORACLE_SID) | perl -nle 'print $& if /SKGP_HIDDEN_ARGS=[^ ]+/' SKGP_HIDDEN_ARGS=<BG/S/x0/x10/x0/x3E5839D4/6015/6015/xF> If the first attribute is BG, killing the process will not crash the instance; if it's FATAL, it will. For the convenience of those that don't... --- end quote --- You don't need to remember the complicated command. Just type `ps eww <pid>' on Linux or `pargs -e <pid>' on Solaris and check the environment variable. Normally SKGP_HIDDEN_ARGS is at the end. Reference: http://yong321.freeshell.org/computer/OracleViewedFromOS.doc Yong Huang -- //www.freelists.org/webpage/oracle-l