Hello John,
you can use sh proc mem | inc Free to see the amount of free memory
sh proc mem | inc Free
Processor Pool Total: 903574352 Used: 408511716 Free: 495062636
I/O Pool Total: 67108864 Used: 14337856 Free: 52771008
PID TTY Allocated Freed Holding Getbufs Retbufs Process
When less then 10% of memory is free I would worry about it
sh proc mem sorted when supported provides a list of processes using most memory
Example (from a 7609 using BGP to receive two internet full tables)
sh proc mem sorted
Processor Pool Total: 903574352 Used: 408522624 Free: 495051728
I/O Pool Total: 67108864 Used: 14337856 Free: 52771008
PID TTY Allocated Freed Holding Getbufs Retbufs Process
496 0 561774644 311139852 181729656 0 0 BGP Router
0 0 163768048 9353656 123358440 0 0 *Init*
268 0 568890024 104879196 53858376 0 0 IP RIB Update
0 0 940224960 849886820 51439880 13800116 75552 *Dead*
322 0 893716 170028 880504 0 0 FM core
240 0 809264 628 834240 0 0 L2TP mgmt daemon
Hope to help
Giuseppe