>prtconf -v | grep -i mem
Memory size: 2048 Megabytes
memory (driver not attached)
virtual-memory (driver not attached)
memory-controller, instance #0
memory-controller, instance #1

This seems to return the amount of physical memory I have, but not what is being used.

We are getting closer!

doing 'man vmstat' yields:
used = 'Memory size: 2048 Megabytes' - 'free size of the free list (Kbytes)'

I'm not sure though - others might correct the 'math'

Since your question is performance related, you really don't need to know how much physical memory is in use. vmstat will give you the performance information you're looking for (I cleaned up the output a little, format wise).

Distilled from Sun Performance and Tuning by Adrian Cockcroft:

The sr column (Scan Rate) is probably the most important when determining whether you're short on memory or not. When this number gets to a high rate (200 pages per second averaged over 30 seconds), then you're short on memory and need to add more.

Swap space and available swap isn't a real help since the system will balance things out and the free column will stablize out.

For CPU's, four times the number of CPUs in the run queue (the procs/r column) means you should add another cpu.

For disk slowness, the blocked queue gives you the info (procs/b column). If b => r then you should look at balancing your data or perhaps getting a RAID in place.

Carl

Did you lookat pmap
pmap -x <PID>

I think that's fine if you're troubleshooting a memory issue, but it sounds like from his initial request, that he wanted something to keep an eye on. "Healthchecking" he said. I think the vmstat info would give good health checking information.

Carl

I am very appreciative that you are all helping me with this. Let me first explain what I am trying to accomplish, and then let me ask for clarification about vmstat and top.

I am a middleware sys admin (not a Unix admin). I do a daily healthcheck of the Solaris servers where my software (MQSeries) runs. In addition to looking at specific MQ logs and queues, I also look at some system-level stats, including CPU and memory usage. This is not a "scientific" look; rather, it's a point-in-time peek that has allowed me to develop a "baseline" of normal operations. I look at the system-level stuff because 1) these are dedicated middleware servers & nothing else runs on them and 2) MQ & related software spawns many processes (that's why I don't just look at one process).

This approach has helped me catch problems several times.

My specific question about vmstat and top is about interpreting the data. (Remember, I'm not a unix admin!)

Here is vmstat output:
r b w swap free re mf pi po fr de sr m1 m1 m1 m2 in sy cs us sy id
0 0 0 5622568 1636016 38 137 5 0 0 0 0 0 0 0 0 258 1235 307 1 1 99

I *think* this means that I have 5.6 Gb of total memory available, of which 1.6 Gb is free.

Here is the top output:
Memory: 2048M real, 1555M free, 4099M swap free

I *think* this means that I have 2.0 GB of physical memory, of which 1.5 Gb is free AND I have 4.1 GB of swap that is also free.

I must not understand how to read these outputs, eh?

Gratefully yours,
Shirley