Solaris memory question...

On my Solaris 10 server we are having memory issue. I did top and I see this.

 
last pid:  8876;  load avg:  0.19,  0.16,  0.16;       up 50+05:24:02                                        14:56:53
80 processes: 77 sleeping, 1 stopped, 2 on cpu
CPU states: 93.5% idle,  3.1% user,  3.4% kernel,  0.0% iowait,  0.0% swap
Memory: 16G phys mem, 740M free mem, 16G total swap, 16G free swap

From the above it seems I have 16G memory but I only have 740 free mem. Why is swap memory at 16 gig. is that wrong?

Show us output of following commands:

echo ::memstat | mdb -k
prstat -a 1 1| nawk '/NPROC/{p=1}p'
vmstat 1 10

On many systems cache memory is not listed under 'free' even though it's as good as free for all purposes.

The following prints % used virtual memory:

swap -s | nawk '{print int($9*100/($11+$9))}'

Below 75 is okay.

Swap is 16G, because the system is configured to have 16G swap.

Other then that, this output would suggest everything is ok.

How does this 'memory issue' manifest ?